I tried the 5-20 twice and the lower magnification once. Nutshell:

First one lasted about an hour then stopped. It wouldn't power on for anything. Customer service is non-existent so I took it back and got a second one.

The second one was DOA. Nothing. Nada. No worky-worky. I took it back.

Thinking it might be the 5-20 I got a 3-14. The electronics worked for the most part but it would not stay focused. It's not super-easy to focus finely at night and a shot from my .308 knocked it from in focus to so blurry you couldn't make out what you were looking at after a single shot.

I figured 3 strikes you are out. A cheaper alternative is the new 4.6x42S sightmark. It is their second gen and has higher res than the previous version and has some of the cool features like wifi video. You can get one right now using their 10% off coupon at optics planet shipped for about 495 or so. I just ordered one and can report back if you are interested. Note that I had an older sightmark and loved it (for the money of course) and took a couple hogs with it.