I have powermags in both .357 and .44 mag. I have been VERY impressed with their build quality and accuracy. In both revolvers, the chambers are very highly polished, almost better than anything else I have seen. Just fantastic. The .44 was a bit of a project, it was missing the ejector tube/rod and stud on the barrel. And somehow, the base pin had a slight warp. Thankfully found parts to put the .44 back to fully original and super smooth. Keep looking for a .401 I can afford...but not yet.