OK, on topic:
I've tried numerous game rental companies, here are my opinions:
Deepshark - they had terrible customer service. I tried to cancel my free trial and they wouldn't let me, even after I got the games back to them (which they claimed had to be back within the 10 day trial - which would be impossible for someone who lived on the West Coast since Deepshark is in CT and it would take 4-5 days just to get the first game, notwithstanding weekends or even playing the game!). I had to fight them for it and had to quote their own FAQ back at them. Their game selection is also spotty. Many were listed as available, and yet they did not ship. Choices four and six ended up getting shipped, and all the while choices 1 - 3 were all listed as AVAILABLE! Bizarre. Plus it's difficult to browse games. However, if you try and cancel, they will offer you a reduce rate of $15.95 for two games out at a time. ($19.95 regular).
Gamefly - No problems, but spotty shipping. Manhunt and Prince of Persia shipped to me on the same day, yet Prnce of Persia took four days and Manhunt took six days (!!). Customer service was pretty nice, but was pretty upset when I told them I was thinking about going with Blockbuster. ;-) They allow 7 days after cancellation to return games and are very flexible. Terrible shipping times to the East coast though.
Turbogamer - Based in Detroit. Received my first and second choices in three days. Terrific service. Game selection is thinner than Gamefly, but same price ($19.99 for two games at a time). Sent games back and will report back when I see what the turn around time is like. So far, so good.
Blockbuster - Games Freedom Pass cost $19.99 plus tax for one game out at a time. The good part, you can trade it in and get what you want right away, no wait time for shipping. Downside, their selection sucks. There's hardly anything ever available except for the guaranteed in stock games (two games a week, usually new releases). But if you like new games, it's pretty decent. They also have a two game pass for $34.99 a month.
If you lose a game via the mail, they'll let the first one or two slide (just like Netflix). But after that, you'll likely get suspended until you pay for it.
Anyone want more info?