Haven't used the 11 speed Sram stuff, but for me the thing was having "Zero Loss" on the right (back) back shifter. Red 10 speed had this and until somewhere in 2012/13 Force did not. I have Force and Red that have it and there is no difference in how they shift. Before that change the Force rear shifter was harder to use and mushy.

What ever "zero loss" is, it is good. If the Rival does not have that, I would pass.