I sous vide'd some ribeyes this weekend. 1 hour at 129F.
One of the steaks was quite a bit thicker than the other (1.5"), so it came out more rare than I wanted it to, but it was evenly cooked throughout, and the fat was all rendered out. The thinner of the steaks was perfectly done, and super tender. The cap part of the ribeye was pretty much falling apart when I was searing it off in the pan. Probably could've cut through the steak with a butter knife.
Next time, I will go a smidge higher in temperature, and I'll buy steaks that are more uniform in thickness.
Pics (please ignore the soother. We have an infant so there's baby crap everywhere)