I'm sure I'll get flamed for this, but why not use the MV-22 Osprey? If it's such a hot item, I'd think it would be great for the president.
Osprey has a less than desirable crash record.
The Osprey got shoved down the militaries throats until the body bags got too heavy. Gotta love it when outside influences take the place of the safety of our men(and the occasional woman).
They wanted a helicopter. Not a pet rock.
At one time they were going to use the ch-53, but it didn't fit on the white house grounds well enough. I doubt the osprey would fit any better. Besides, it wouldn't look good to drop the president like a rock.