Steam is fine. I love Steam. Because it works perfectly.
Now, when a game has extra DRM, like GFWL, is when I have a problem. Quantum of Solace, good game, but it uses GFWL and if I'm offline, I can't save. WHY?! Not to mention that every time I go to play the game, it tells me I have to update it, or again, I can't save.
Worst though is SecuRom. Look it up.
Guh...
I really hate it, because I have had a problem with it after buying the game from GamersGate, and the serial not working after a while. So, I emailed both SecuRom and GamersGate. This was a few months ago. Nope, no response from SecuRom yet. However, GamersGate quickly gave me a new serial, and I'm happily gaming now.
I refuse to buy DRM'd games now, because I don't want to go through that again.