Relating this discussion to the V-22, I had been hopeful to learn what the V-22 configuration can manage as to slope landing capability. One would expect it to have very decent capability laterally, for instance. Should be OK nose up as well, leaving the nose down direction as the primary question and whether they can use all -7.5 degrees of aft tilt and whatever aft cyclic pitch is in the control system to provide a reasonable capability for a tactically used machine.
The slope limitations in all directions is 9 degrees. I've landed on the concrete slope pads at Pax before and it's a bit odd using nacelle angle and landing with the slope already "built in" so to speak vice touching down on the mains or nose and inching the aircraft down from there but just takes getting used to.