My horse has had coratflex but i didnt feel it helped at all so he changed to superflex which seemed to help. Then the vet gave us synequin, but at £144 a time its a bit much!! Hes on nupafeed flex glm now, seems to be doing the job! Hes bouncing all over the place! Its cheap compared to some, comes in 2kg and 4kg tubs. 4kg is about two months supply and its about £70 includin p&p. You can only get it mail order, but it arrives within 24hrs. Theyve got a website too, http://www.nupafeed-uk.co.uk/
I normally get a medium sized(1.5kg I think??) pot from Hyperdrug for £89.00 plus postage which lasts my 14.2 pony about 8 months. They do a smaller pot which is cheaper as well about £40.00(?)- I bought the smaller pot first when I first started using it just to test it out before I paid out more money!
One of my horses has joint prob so got the exactly the same size joint supp from my vets which was about £120 inc postage!! a big difference! luckily tho my insurance paid it as my horse has had to have veterinary treatment!
My horse was on superflex but after her operation last week they found alot of damage to the cartledge and surrounding areas.
My vets have just ordered the newmarket one in for me as its 99% pure and meant to be one of the best. When i cant claim for it on the insurance anylonger i will buy it from hyperdrug as they are billing £53 for a 500g pot and its much cheaper at £38 for this size from hyperdrug. I shall buy in the larger pot of 1.5kg for £89 when i come to buy it myself so save a bit.
Equus Health do a 99% Glucosamine. I don't know how much it costs but their 99% Glucosamine & MSM (Flexy limbs) costs about £22 for a tub that lasts our 15h h/w cob two months. The link below should take you straight to the product details.
Slightly off topic (only a little bit!) But apple cider vinegar (the type that looks like it's got cobwebs in it) is supposed to be BRILLIANT for joints and all sorts of other things. Marius_mum posted a great link I thought I'd saved, but I haven't
The most important thing is to do your research carefully just because one supplement is cheaper doesn't make it better value for money. It may have a lot of bulking agent in it. Similarly if one product lasts longer it doesn't make it better, as it is not hard to make a product last longer by reducing the daly dose level. It is vital that a joint supplement is fed at the correct level to be effective. It is far more beneficial to feed one joint comound (glucosamine) at a high level than all three (Glucosamine, MSM, Chondroitin) at a reduced level. If you feed inadequate daily dose levels the product is likely to have a very limited affect if any at all. Read all labels carefully. The product that feeds the highest daily dose regardless of cost or brand is the one that is best value for money. A horse or pony between 300-500kg should be on at least 10g glucosamine daily and should be hydrolchloride not sulphate as this is more easily absorbed. There is loads of information regarding what to look for, how much you should feed, etc on www.riaflex-equine.co.uk
Good luck with your search
I use Newmarket too, works out about 60p a day for a 14.2 (£150 for a 8 month supply with the 2.5kg tub). Its the only supplement that has worked for Chex, definitely worth the money.