Upload & Sell: On
I'll be disappointed if a 24-70 Mk II lacks IS. In available light classrooms and music venues, I can get away with 1/40th on the 16-35/2.8, and sometimes even slower than that with the 70-200/2.8L IS II. But for the invaluable medium range, the 24-70/2.8 is often impossible for me to consistently handhold with acceptable results. The 24-105/4 is not fast enough to use indoors. It's always a crapshoot with subject motion at such slow shutter speeds anyway, but IS at least gets photographer motion out of the equation.
The 17-55/2.8 EF-S lens is a joy by comparison - and the only reason I keep a 7D around. It'd be nice to have a 24-70/2.8 with IS to use on the FF and APS-H camera bodies.