I really believe that the price or brand of a shampoo or conditioner makes no difference to the efficacy of the product. As with many other products, people often end up paying for the "brand" with shampoo and then being disappointed with results which don't reflect the price they paid.
I've been critiquing shampoo and conditioner with eagle eyes since about 8 years ago when I was silly enough to use a home pre-lightener on my dark brown hair, which then turned it into a big bush of bright orange hay. It took four years to grow out completely... along with a multitude of hair dyes to get it back to a presentable colour. As you can imagine, my hair and scalp were not in good condition! My hair was so porous! At one point, I was finding hairs which were split into three or more "ends" <shudder>.
During those four years and more, I was desperate to get my hair back to its former healthy, glossy state. I went through so many products, from Superdrug's own-brand to salon brands. And I spent far too much time seeking out niche SLS-free and silicone-free products. What I learnt is that there is no difference between amount of money spent and results. It just depends on the product itself and the right balance of ingredients for your hair type.
Only in the last two years have I found my perfect shampoo and conditioner, which are humbly from The Body Shop. The first time my boyfriend came home with the Ginger Anti Dandruff Shampoo, I turned up my nose: "I can't use that - it has SLS!" And I don't even have dandruff, just a dry, sensitive scalp which reacts to most products. But I used it out of interest, and it felt so refreshing to be using a shampoo that actually lathered properly (I know foam is not indicative of a good clean, but no-one can deny that it feels good!). And it rinses clean too. I was worried that I'd be left with an ultra dry scalp like with all other products containing SLS (and particularly anti-dandruff shampoos), but to my surprise, my scalp was fine - and doesn't itch anymore - not even when I've left it three days before washing (rare - honest).
So that was the end of the 6-year reign of the SLS-free shampoos. I guess my scalp can cope with a little of it...
However, I'm still a major advocate of low-silicone or silicone-free shampoos and conditioners. If you find the right ones, your hair will look good for longer, and you won't need to constantly switch products to get the same "first time" result. The problem with silicone-based products is that they leave build-up on the hair shaft, which makes your hair lank and dull after a few uses. And if you're using the same products over and over again, your hair never gets a chance to shift that build-up. To counter this, shampoos end up having too strong a detergent action, in an attempt to strip the old, dull silicone before a new, shiny layer goes on. So over time, the hair becomes more dry underneath the superficial shine.
Other downsides I've found of silicone-based products are: hair becomes limp quicker and thus requires more frequent washing, build-up on scalp turns into grease and flakes (gross!), and little spots develop on sides of face and back where hair touches.
The Honey Moisturising Conditioner from The Body Shop is the conditioner I've been looking for my whole life. It contains some silicones (Quaternium-80 and Amodimethicone) but they're relatively far down the list of ingredients compared to brands like Pantene, Fructis, Redken, Kerastase etc. The Honey Moisturising Conditioner has been life-changing. Every wash, it leaves my hair glossy and tangle-free and miraculously stops those frizzy, sticky-up hairs around my parting. But most importantly, my hair still has bounce. There's no point me having shiny hair if it's just hanging there.
So after that, I decided a little silicone in the conditioner is fine - although I still recommend avoiding it in shampoos to prevent build-up.
But anyway, here's the lowdown on the many other shampoos and conditioners I tried and discarded during my obsessed years (well, the ones I remember and in no particular order!):
The Body Shop Honey Moisturising shampoo
I used a few bottles of this (before discovering the Ginger shampoo) because it was SLS-free but still quite foamy. However, it left my hair dull and heavy after a while, and my scalp would itch if I went more than two days of not washing my hair.
TIGI Catwalk Oatmeal & Honey Treatment shampoo and conditioner
Ahh... the early days! Smelt divine. The conditioner was low-silicone and packed with moisturising ingredients like avocado oil. It felt nourishing but would stop "working" after a while. The shampoo was horrible - too siliconey and left my hair greasy and my scalp itchy.
Mastey shampoo and conditioner ("moisturising" and "repairing" ranges)
A niche SLS-free and silicone-free haircare brand (rare at the time) which was soooooo difficult to get hold of in the UK, but I managed it for a couple of years. The shampoos were great, but there's so little lather that I got through those expensive bottles too quickly for my liking. The conditioners were effective too... but I eventually got fed up with how difficult it was to buy. Amazing quality stuff though.
Redken All Soft shampoo and conditioner
A proper "salon" silicone-laden product! Left my hair incredibly shiny and swingy the first wash, but would stop "working" after the first go.
KMS Silker Reconstructor and shampoo
Shampoo was rubbish - greasy and itchy. But I had a long term relationship with the low-silicone Reconstructor which claimed to reduce the porosity of hair. It really did make my hair silky and less porous... and smelt of cherries yum. But the dreaded itchy scalp soon returned.
Superdrug Naturals Henna & Sweet Chestnut Intensive Conditioner
Low-silicone, cheap as chips, and actually quite good! Used for a year. Gave good shine and bounce. I would have continued but it wasn't quite right for my sensitive scalp.
Superdrug Colour Enhance Intensive Brunette conditioner
Not quite as good as the Naturals Henna & Sweet Chestnut Intensive Conditioner (above) but ok for the price. Horrible "chemical smell". My scalp didn't like this at all.
Duchy Originals Rose & Mandarin shampoo
SLS-free and silicone-free. Smelt of Turkish Delight (and old ladies). Reasonably priced but nothing special. Almost no lather, so I just ended up using loads each time.
Original Source Almond & Coconut conditioner
Silicone-free. Really nourishing. Left my hair in better and better condition with each use. Used for a year. Unfortunately, my hair took too long to blowdry after washing due to the high levels of natural oils in the conditioner. Apart from that, a fantastic high street conditioner. Shampoo not worth talking about.
L'Oréal Elvive Nutri-Gloss Intensive Shine Masque (pink pot)
Low-silicone (unusual for a L'Oréal product!). Fairly moisturising but there's something not quite right with the texture of my hair after using it... like heavy-feeling. And like the Original Source conditioner (above), the balance of oils is not quite there. There's too much palm oil, meaning that it takes longer to dry my hair. Plus the texture and smell of the product are really cheap.
JASON Natural Sea Kelp Conditioner
Very low-silicone but nothing special.
Avalon Organics shampoo and conditioner (various)
SLS-free and silicone-free. Nothing special. Low lather (but more than Mastey and Duchy). Didn't really leave my hair feeling moisturised. Still used for ages just for its SLS-free and silicone-free status and ease of purchase at the time.
Naked (from Boots) shampoo and conditioner (various shine-enhancing / moisturising / detoxing)
SLS-free and low-silicone. But not great. Leaves my hair tangly, limp and dull, and not great on the scalp despite seeming gentle. Completely de-bounces too. Doesn't feel luxurious to use.
Australian Organics shampoo and conditioner (various)
SLS-free. Meh nothing special.
Bumble & Bumble Seaweed conditioner
Low-silicone. Texture is too "watery"... no shine or bounce. Not really moisturising enough for me. Maybe better for fine hair. Smells nice though. Shampoo leaves my scalp really itchy.
James Brown Dry Hair Conditioner and Intensive Mask
Similar to the Naked conditioners... leaves my hair tangly and dull. The non-intensive conditioner is low-silicone (being more based on oils and butters). The intensive mask is more siliconey. Fragrance is too artificial and perfumey.
Aussie 3 Minute Miracle conditioner
Silicone-free (I think). Bought it back in the day when everyone thought it was amazing. Artificial bubblegum smell. At the time, somehow managed to leave my hair more dry and hay-like. Rubbish.
LUSH Retread conditioner
Silicone-free. Urgh gross gross gross... feel sick just remembering using it all those years ago. Smelt awful. Horrible too-natural texture (like yoghurt). Left my hair super lank and dull. And it went mouldy in the pot quickly (but good excuse to throw it out).