Been reading alot of positive reviews w/ this product.

Anyone currently use one or given a test run?

I've used both the Anchor Sight and the Timberline No-Peep. Both do just what they advertize, in that, they are both anchor references. The A.S. is perhaps a little more versitile and set-up friendly but both are used essentually the same way. Is there something in particular you want to know about them?

Did you prefer the AS over a peep for hunting?

I've also heard claims of better groups over the peep. Any truth to that?

No I can't say the groups are BETTER than a peep. If I did more tornament archery than hunting I'd use a string peep. The vast majority use a string peep. What I like about the AS is the low light conditions. Some just use a larger peep to overcome low-light issues, but I like the AS type device. If you set it to your anchor, it just becomes a verification of anchor, and you only have your pin to deal with. AND, you'll never have peep rotation to be concernd with. For a guy who hunts and target shoots in the back yard out to 40 yards, they work great. They may work well farther than that, but that's about the range I use my bow at. So I can't honestly give you any more than that.
It is a nice alternative to using a peep site.