Not much different than, at least system rules, the rest of Palladium games though I believe it introduced the idea of "Mega-Damage" which has its own controversies (and is used extensively in other P-games like RIFTS.) Never tried to track it down but I can't imagine it being super-difficult or very expensive.

Like the others, it has its hunks and chunks -- too many skills, many that cross-over and add to each other, "problems" with attributes being too high, damage being ridiculous, being useless when not in armor, etc etc. Nothing that cannot be overcome with a little tweaking. Not a game I would suggest mixing with the others in the "Megaverse" though as the robots are just... yeah.

The fact that they may make an occasional book for it doesn't really mean anything. Maybe they don't want to lose the license. Maybe they still hold off on hopes for something. Maybe they have to by their license. I don't put any weight to that as proof of sustainability or even that folks like the game.