Yeah, thats my wheel. I didn't hit any pot holes or hard bumps. Noticed it last night when I was pulling up to my house, was making a weird noise. The wheels were purchased brand new in February by my friend (also has a FiST) and powder coated. He hardly put any miles on them and I've only had them for 2 months.
Oh no, so sorry that happened to you. It's also cause for concern for me because I've been planning to get some 1.2's. NJBooST mentioned in an earlier post that powder-coating can weaken a wheel as much as 30%, I had no idea that could weaken a wheel that much. Since you bought from a friend, hopefully you would know about any big impacts to the wheels before you got them.
A few quotes from another site on powder-coating-
The amount of basic heat required to powder coat a wheel is enough to pre-maturely "age" and weaken the metal alloy to the point that it is more brittle.
This is exactly why wheel makers like Enkei say that powder coating voids their warranty.
It is not so much the powdercoating itself, it is the process... which involves stripping the paint by sandblasting and could lead to thousands of micro-cracks, which can only get bigger. chemical removal of the existing paint is preferred. additionally, many degrease the wheels by baking them in a high temp oven and that in itself can cause damage. the powdercoating occurs at a low enough temp as to not cause substantial aging, but it does in theory age it some.
This is from some pretty knowledgeable guys on NSX Prime.