To be fair I had to pull them once and replaced one with a stella can, it was still on it when I sold it, they may be flimsy but they did the job.
I have been looking for a shallow set for ages now on eBay. When the last lot sold, the price was so ridiculous, I decided that I would be better putting the cash towards a new set of wheels
As a new owner of a 3D printer, I can imagine another way of getting wheel caps, providing somebody can do the CAD for the design, and you dont mind sanding, filling and painting the result.