Fasa had a really good run there for awhile.
I don't know what version, but I actually owned all (25+) books for the mechwarrior/battletech RPG.
It seemed to me, that while the miniatures portion of the game was well balanced, and you could have a small battalion of PC's dungeon crawl their way through an adventure (*kinda like the most recent incarnation of D&D actually) the RPG portion of the game was... wanting. any time spent outside of the Mech's seemed to be wasted time. So, if you wanted to play a mechanic, you'd better be a pilot first, and a mechanic second. A psychic 'face' type PC? well, only if your two main focuses were piloting (Mech) and Gunnery (Mech). any other points were wasted.
Now, that could have just been my experience and particular group that I was running with, but the mechanics of even just getting into a bar fight were kinda weak in my opinion.
The explosion portion of the game though? Firing PPC's while jumping, and flanking over a mountain with your lighter and faster 20 ton mechs? AMAZING! nothing like it.
I don't know how many hours I spent trying to fit an AC20 onto my Locust or Jenner. but it was a lot.
We did get the game to work finally, (eventually)
Just made it 'all' in the Mechs. Gave everyone a set number of 'build' points or credits to buy and design their mechs, and then had them go to town on a big ol' map with GM controlled badguys. That seemed to work pretty well.