"What if you took Stargate and made it darker, sexier and edgier?", said no fan ever. This show swiped the best of BGS and mashed it up with some great music, in front of a gate. It probably wasn't very good material for Stargate fans.
But it was a really good show. I'd give it 4 of 5 stars.
The actors were top-notch, the pacing slower, the sense of discovery was put at the forefront. Probably too much at the forefront. They wiped their butts with whatever Stargate had established.
But it was good TV and science fiction. They stole a couple of key concepts from the series that came before it and ran like hell with them. The communication stones from the original show were placed front and center in the plot. These devices popped up in Season 8 of Stargate. "Citizen Joe" was probably meant to be a "cheap, one-off " episode to save on cast and film costs, but it was frakking brilliant. SGU took that simple idea and made the speculative science fiction and flipped it towards contemplative. What does it mean to be "someone" if you can trade places?
Like that one episode of Stargate, SGU tries to get into the head of the watcher by leaning on the contemplative. Some of the time, it worked. There were a lot of misses, but you could see the direction the show was taking.
The show has many callbacks to some hard sci-fi, stuff so hard that it often isn't recognized as sci-fi at all. My personal favorite episode was "Trial and Error" which is a close crib of The Defence of Duffer's Drift. Capt Young experiences a series of dreams where the ship comes under attack. These dreams are the Destiny's attempts to communicate with the crew directly to determine their capabilities. It doesn't work well because as a program, the ship was expecting a commander to have all the answers, not to be the head of a team that creates answers on the fly. Young was exposed to his own failings and it became personal. Very personal.
Another episode zig-zagged from high action romps back to the speculative. In Season One the episode "Time", the crew finds a Keno camera that recorded their deaths in an alternative universe which provides some answers to their current situation, again ask "who are you, if it's not really you?"
Much of this show asks the question, "What does it mean to be x?". While Stargate was probably not the best vehicle for this contemplative study, it was very engrossing.