I've got several sets of Leupold QDW rings ... these are their QD rings that fit Weaver style bases. I like them best on steel bases. I also have a set of rings that I bought so long ago I can't remember who made them ... anyway, they have a simple thumbscrew that tightens them to the weaver bases. This set I have tested by shooting removing shooting removing shooting removing etc and the POI only shifts a total of about 1 MOA ... probably not a good idea if you are going to take 800yd shots, but a total non-issue for "normal" ranges. I have never collected the data on my Leupolds, but they feel much sturdier than the old ones.
Hope this helps,
Saands