I never finished SGU back when I first got access to it. I've finished both SG-1 and Atlantis countless times. I remember watching most of the SGU pilot episode and quitting. I thought it was being too overly edgy and grimdark, trying to follow in the footsteps of the Battlestar Galactica reboot. I couldn't stand the idea of a Stargate show that was just characters being awful to each other.
Recently I tried giving it another shot and made it through the pilot episode. The characters are still abrasive to each other, but much less than I remembered, and they seem to for the most part mellow out a bit with each other as the episodes progress. I just finished the forth episode and I do want to continue. I am hoping they start actually doing something more than "the ship is falling apart we need to do something to fix it" plots, but I suppose the show really is trying to plant the setting.
I definitely enjoyed SGU and have watched it through a few times. Its a shame it was not able to continue.