I was originally looking for a wireless Canon remote, but when I saw this one, I figured it was worth a shot.
It works great. The only setup required is to pull the tab to activate the battery. The remote is not much thicker than a memory card case, and includes a lanyard loop, so it's not at all in the way. There is no indicator light on the remote, but the buttons have very snappy tactile feedback, so there's no doubt that you've pressed the button.
So far, I have only tried this remote indoors with my Canon T2i (550D), but it works very reliably, and from a reasonably wide angle, though I'm sure that varies from camera to camera.
It would have been nice if the button groups were separated by ridges, and possibly color coded, as they all kind of run together, but overall, it's a great remote.
Pros: Easy to Use, Lightweight/Portable, Many Useful Features, Good for Experts, Fast, Easy Setup, Solid Operation, Good for Beginners