Mekton II isn't really my thing, anymore -- I ♥ giant robots and all, but I'm just not in an anime place right now. (Plus, I have Mekton Zeta and Mekton Zeta Plus for that kind of thing.)
Mekton Empire, on the other hand, is a gem. I have reasons for saying that.
What we have in Mekton Empire is this: a solid yet flexible SF/space opera, inspired apparently as much by Gundam and Captain Harlock as by Traveller. You have a bunch of planets, each with a write-up (and even some abbreviated codes, wheeee!), a map, some new equipstuff, some new rules, alien races, corporations, etc., etc., etc. It's a hearty supplement to the core game.
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The planets are swank. They range from quaint and welcoming to dark and mysterious to exotic and exciting. Their 'stats', as it were, are written up in such a way as to evoke a "Traveller UWP Lite" kind of impression in the reader, and manage to be evocative on their own. I immediately wanted to start making up my own planets, once I looked at the format.
The best thing, though, is this: It's a breeze to yank the anime influences out. If it looks like a furry, change the way it looks. If it's an anthrpopmorphic mek, turn it into a starfighter. Toss out the fairies (look, man, I dunno, okay?), and you're left with a workable space opera setting full of reptiloid pirates, mysteries to solve and a planet which does nothing but manufacture and export candy.
The candy bit, I'm keeping. That's awesome and it makes sense.