I've tried Quest bars, Victory bars, B-UP bars, Atkins bars (complete garbage, except s'mores) and OhYeah (didn't like any of the ones I tried).
Quest bars are hit and miss - stick to cookies and cream and choc chip cookie dough - all the other ones are really hard to chew if not heated and have barely any flavour. Victory bars were nothing special but I haven't bought them in a few years, maybe they've improved. The only good flavours of the B-UP bars are PB and J and sugar cookie (which doesn't taste like sugar cookie to me, but has a very pleasant taste).