I own it. I did a lot of research on those types of games, and determined that GalCiv 2 was the best. I've played about 10 games on it, and it's a lot of fun. The negotiating with the other civ leaders is interesting (and even funny sometimes!). And even though I didn't think I would agree with some reviewers, the thing I ended up really enjoying most was designing all of the ships in my fleet. You can build hundreds of different kinds, and save some as templates. Pretty cool.
Sometimes I play a good civ, and am very diplomatic until someone attacks me. And I try to protect my friends from the baddies. Other times I act like Darth Vader and try to obliterate everyone, or (even better) keep someone alive but extract ransom money from them to build up my fortune.
You'll have fun, trust me.