I find El Cap what Yosemite should be from the start (aside from UI ugliness of both). Quick, responsive and snappy
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. ~20% OpeCL performance increase doesn't hurt too.
It runs better than Yose on my franken-1,1 (pretty much maxed out: 32GB, 5365s, R9 280).
Even as it's installed on 2,5" WD Black vs Yose on XP941.
I will replace Yose as soon as they release GM or 1st update.
This machine serves graphics design and DTP in CS6, so before full transition I need to be 200% sure that all software I need works without any hiccups. DP is DP, I don't trust it enough to make it main OS.