I've had a Wheeler 89 pc set for a couple years. It hasn't seen a lot of use, mostly S&W sideplate and strain screws, but several bits have already twisted, and the finish of the bits does not appear to be ground, but rather simply as cast. I examined them under a loupe, and can see that the face of the tip that bottoms in the screw slot is not sharp, flat and square, but kind of wavy and rounded. I looked closer at the label in the case - surprise, surprise - made in China. The bits are junk, warranty is only ONE YEAR, so I can't return them, or I would. I do like the handles very much, finding the slightly soft grippy surface suits my hand better than the hard plastic of the Brownell's set.
I guess I'll go buy a stock of Brownell's bits and hope they fit the Wheeler handles.

Forgot to add - I've had a Forster set of 8 gunsmith screwdrivers for about 40 years. The tips are still in excellent condition - no chips or twists, but now with arthritis in my hands, I find the handles too small in diameter to get a good grip. That's why I bought the Wheeler set.