First of all, I am not going to repeat what other reviewers said: if you like the Mecha genre, there is probably no better product out there which offers the same mix of roleplaying and strategy and "crunch". But I want to address some things regarding the 2nd edition, and a few issues I had with the 1st edition.
So what's new in 2e?
1) It's still the same game, which is a good thing. Sadly, the author doesn't specify what's really new. On a cursory reading, I couldn't find any difference in the rules; perhaps it's in some Mecha configuration or some other little detail? It would be useful if the author produced a small document which tracks the changes. I have already a print-out of the 1st edition with which I am familiar, and it would be nice if I could avoid to print it out again.
2) Despite the fact that an editor was hired for this new edition, the number of typos has not been reduced drastically. On a random sampling of pages throughout the book, I reckon less than half the typos has been corrected. And the number of typos in the 1st edition numbered at an average of approximately 2 per page. That's really, really annoying. PLUS, there is a boat load of page XX references. 31, to be precise (and what's worse, they are in the cheat sheet which is supposed to be helpful.) That's just sloppy editing. The layout on the other hand is better, and a few glitches in the graphical presentation have been fixed.
So, all in all this 2nd edition needs work, perhaps more than the 1st edition did (at least there weren't any page XX references.) I am only giving a rating of 3 because of the presentation and the annoying typos, and the lack of a "what's new" list.
[3 of 5 Stars!]