Upgrade to the 21.5 to retina and minor bumps to 27 retina likely in October (if not Sept 30th). Likely better color depth on both. Graphics chip 395x (minor update to 295x) in highest end. Skylake is barely available anywhere in the real world.My guess is that we won't see any new 5K iMacs until next Spring, perhaps late Winter. I think Apple will wait for the appropriate Skylark chip to be ready.