It looks fantastic but, I hesitated because I heard it took lots of time to resolve one game, a con that plagued Sins of a Solar Empire when it was released, but is this allegation true or not?

It takes weeks to finish a game, and you'll enjoy every second. Get the expansions, too, they make it an entirely different game. Be sure to equip yourself with snacks and mountain dew, though, you won't want to leave. GalCiv is great.

Thanks, quick question, did the new expansion come out? Think its endless universe.

I'd say go with all the add-ons. The game is amazing and no one really cares about the campaigns compared to just playing the core game and generating a random galaxy. To answer the initial post, you can set the galaxy size to be relatively tiny so games can take a few hours at minimum but you can also make massive galaxies that will take many, many play sessions to complete. It'll be fun no matter what it's a sweet game that I wish I had more time to play.

 
i'm going to assume the first game will teach me how to play - but i'm going to also assume game play changed with each addon... is there a training thingy in twilight?