I have two, both bought from Brownells back when Brownells sold them. They are both Platinum ones with adjustable sights. One is a 5 inch or Gov size and the other is a Commander/Officers size which is 4.25 inches.
They have been great over the years and I use them on different bottoms. I also picked up a Marvel conversion which is more accurate and Kimber Conversion, plus a Colt Ace unit which is more a collector thing. Anyway they have been fine. I sort of got away from shooting them when .22 became hard to get or very expensive.
I never dealt with Ciener as a company so do not know how they are to deal with.
I am going to dig all the conversion units out again at some point in the future as I bought one of Brownells 1911 .22LR 10 round mags and on the back it says it works with a bunch of conversions including Marvel, Kimber and Ciener and I am curious if it does. If it works I may order more.