Recommend the Marvel Products Conversion
I believe the best currently produced conversion kit for the 1911-platform is the Marvel Products conversion kit. This conversion kit is accurate enough for Bullseye competition as judged by Bullseye competitors. Mine came with a button containing the factory test target; the group was 0.775" at 50 yards.
The Marvel is more costly than the Ciener; however, it is extremely reliable and very accurate. The sight rib is replaceable, and one can mount an iron-sight rib or an optics-mount rib.
I have one that I mount on a Series 80 Colt Government Model; it is as accurate as my S&W Model 41.