Hi, I have one mounted on the Weihrauch HW44 and it's performed very well.
It's well made, easy to mount and sits very low on the gun. The adjustment is great, although I find the auto brightness mode always seems to get it wrong so I do it manually, not a big deal.
It's easy to adjust and keeps zero no problems at all.
It comes with a bullet proof warranty and good customer service so to be honest I would just buy it!
Cheers
Lewis