I'll dump them too if it works like that.
Gamerang's service just sux though. I never got an email ship notice when they shipped something. I immediately got that with Gamefly.
Gamefly's service and system seems more polished like Netflix. With Gamerang, I feel like I'm dealing with Brand X.
I think gamefly also gets slower and slower the longer you stay with them.
Of course, you can always switch back when gamefly gets slow, then switch again when gamerang gets slow again.