Last year I bought, mail-order direct from Tripp, the 9rd ones for a (.40) Ranger II that wasn't reliable with the OEM magazines. The CobraMags exhibit quality. They are highly polished, bright and very shiny. Feeding improved some, but not enough. The dealer, Freedom Ventures, eventually replaced that particular Ranger II (with one chambered in .45ACP, and which works fine).
I wouldn't hesitate to buy Tripp Research magazines again (the only caveat being their shiny finish).