Phyffe got me onto this. Battletech was ok as a vanilla experience, roguetech makes it hardcore. As far as I'm concerned THIS is how battletech should have been released.
You get all the weapons, customizable engines, endo steel, ferro, cockpit, targetting and sensor mods, lostech, different parts manufacturers, dodgy pirate tech that does random damage and sometimes explodes, just about every mech ever including super heavy, clans, battle armour, all the vehicles. Gameplay mechanics have been altered to be more similar to tabletop rules. It's almost a completely different game and much much more challenging. Overheating no longer does internal damage but increases odds of internal ammo explosions and shutdown override failure.
It was a bit tricky to set up though. You have to opt in to beta version 1.4 install the mod, then the community resource add on.
Curious to know if anybody else has tried it, I think it's pretty fricken amazing