I've had good luck with my JW wheels, but they are newer ones. The ring gear stuff was mostly with the older ones. I just bought a JW billet wheel that the ring gear is machined into it, like the mez one. I think it's about half the cost of the mez too. I've never seen a bullet proof flywheel, but better is always better.

I know one thing that can effect any of them is trans misalignment. Bolt your case, or bell up there with an indicator. Surprising how far off most are. Offset dowels, or welding on the bell,l or case is a pain, but well worth the effort. Any misalignment causes flex, in on one side, out on the other. Add rpm to that, and most anything will fail in time.