I WISH I could try some MAC. There isn't a MAC store around me for almost 300 miles :(
Not having tried MAC, so far the best I've tried is Clinique Superbalanced Liquid. I - love - it. Didn't like any Revlon, nor did I like Almay, I was into covergirl for a long time, but got tired of the lack of actual coverage and lack of staying power. I've put Clinique superbalanced on in the day time, gone out at night, crashed at a friend's place and woken up the next morning with my skin still looking good.
A friend of mine swears by Lancome's 14 hour liquid. I swear by their concealer (Waterproof Protective Undereye Concealer - my HG), but haven't had the chance to try their foundation yet.