I bought an eBay DID X ring and no probs so far. DID were always fine before and I always fit steel sprox and take great care to get the rivet link set up well.

Had lots of C&S kits in the past and just 'cos it's expensive or anodised doesn't make it wear any less. A well known brand like DID are usually good...

PS I keep a spare front sprok as the wear on these is much higher, especially on a single and when they wear they will accelerate the chain wear.