Dave,
I bought one of these about a year ago. Looked cool so I had to try it - thought it'd be great on my 10/22. It was a great little setup as long as you weren't out in direct light. Since there's no tube the sunlight can make the reticle look really dim. I don't think it was worth the 140 I paid for it. I ended up selling it on eBay and got 100 out of it. I'd pass and go with something like a holosight or regular red dot (tube type).
Ranger413
