I bought a used S&W .380 PPK several years ago. I had hammer follow with it and it was sent to Walther USA by the dealer and it was repaired and has had no issues since it was returned.
My issue with the gun was the lengthened "knuckle" that was added by S&W to prevent hammer bite. The knuckle itself took the hide off the second joint of my thumb, far worse problem than I have ever had with any gun due to hammer bite! Re-shaped the knuckle to be like original Walther guns and that
problem disappeared.
I would rather have a real Walther of course, but I only paid $400 for the S&W gun.
I have several Mec-Gar magazines for the gun and have never had any magazine related issues with it.
Bottom line, if you want it and the price is right buy it! Walther USA services warranty issues for S&W if needed.