if it wasnt for steam there wouldnt be PC gaming as we know it. Over $2000 in games on steam and never had issues, a single game I couldnt start on steam no matter how much I tried, i contacted them, they removed the game and refunded my money. so as much as I was wary of steam originally I believe its the best system out there for *me*.
My problem with steam is that, in addition to your game you have to run another app. This would not be so bad, if you always had internet access. Some folks still don't always have internet. Your game will still work, you either just have to let steam start up with your system (so that the wasted time is at system startup), or wait for it to time out when you open a steam game.
Other online retailers can sell games that do not require an app.
So yes, Steam does work, it just does not work well in my opinion.