Marines & Naval Ships...
That's why the V-22 is attractive... it fits the Marine Corps model. I'd rather have a Warthog (A-10) raining bullets on the LZ than anything else. It is S-L-O-W, armored, and deadly effective against anything on the ground. When the $hit makes contact with the fan, aircraft manueverability can be important, as well. The Osprey seems kinda weak in that arena. For moving troops from point A to point B in a fast and effecient manner, agility is not so important and the V-22 will do well.
For tactical operations, especially commando type insertions, a high degree of maneuverability and additional power will be EXTREMELY important. No matter what it is spec'd out for, you can bet that we will add more weight requirements for the special ops folks in short order. Just look at recent military history and the modifications made over the years. Heck, just look at how much they have to change just to get some tilt-rotor gun-ships!!! Why the heck don't they design these things with 5 times more power than you need so we can grow into them with safety to spare (and so the planners and war-fighters have the flexibility they need for future conficts)?