[Marcus26]

I had a Profi.
At the time it was cheaper than a Sureloc and the best option outside of one from my dealer.
It is one of the things I regret buying and wish I had spent the extra.
It's heavy, poorly balanced and the guy who bought it off me has since had the extension bar snap twice on him.
The windage section for someone else has cracked as well, apparently this is common.

The AGF sights appear well made and I grew up thinkng they were one of the best, but in the last 5 years am starting to think they are complete junk.

The Sureloc was good, but the bushings can wear causing a buzz. Won't impact on teh sight's reliability, just annoying.
I love my Copper John, awesome sight.
If I was buying a sight right now again it would be a Copper John or a Shrewd competition sight.

The Shibuya's are nice, I just don't trust the carbon extension bar. Otherwise nice mechanism on it.