I liked mech warrior 4, mostly for the story line, as well as some of the mechs just looked awesome.
mech warrior 3 was cool too, but for its own reasons.
I stoped like mech games when the "mech/tank" feeling was erased, the mechs these days simply feel like your playing a "big human" like in any modern day shooter, there is no split axis between your upper body and lower legs..things like that.
then again, i miss alot of the older games, game dynamics.