I successfully sous vided two 2kg inside rounds:
One I cooked for 36 hours at 160°F, and the other for 10 hours at 180°F.
Slow cooking lost 28% of the weight, while fast cooking lost 36% and made the meat much denser and dryer.
(This demonstrates that it's temperature that forces out the juices, not cooking time.)
Because the fat content was much less, even ...