I'm using one on my CZ-858.
You do notice the parrallax.
The adjustments also do not "click"; it's a pain to get it just right... the sight does have locking screws. The RDS does seem to be holding zero.
They are made in the Phillipines.
If I could, I'd like an Aimpoint Micro... but for the cost of this RDS, I'm not complaining. It's small, compact and very light.