I got some one-piece after market lug nuts to replace what I consider is a poor design in the OEM ones. The price point is way too high for what you get. The last thing I want if I have a flat is to not be able to get my socket over the nut because the decorative cover is damaged. In my experience, it's not that the underlying core swells, but that the stainless gets deformed (likely by tire monkeys using an impact wrench).