Due to being paranoid about stock and having a short memory, I bought several chains. And, by coincidence, they are all different. I am about to replace my chainrings soon with a Absolute Black oval 50/34, and will swap in a new Ultegra 11-28 cassette too. All the chains are waxed now. So I will be comparing a 105, Ultegra, Dura Ace, Wippermann Connex, and KMC X11SL as I rotate them out. I’ll report back in a year or two 
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