I get mine from pre-equestrian too as it seems to be the cheapest. Having done loads of reading into it I chose F4F and it's been brilliant. He hasn't lost a shoe in 18 months now (we were loosing 1 most months) and his hoof condition is much improved. F4F is very similar to FF but cheaper.
My piglet mare who eats anything and everything refused to eat Profeet! She's been on Formula4feet for a couple of years now and it has made a difference.
naf profeet is def not as palatable as F4F which they love, but they will also send a sample, its one of those things you have to ease in slowly (it smells a bit like curry powder!)
I might be being unfair to F4F but had frank on profeet from oct-Feb and saw a real improvement, been using F4F since feb/March and they seem to have gone downhill again but the weather has mostly been dry which has affected them. Am hoping he will eat the profeet without much feed, am going to give it a go!