Fallmonk,
The F-135 engine (sans lift fan) can fit into a V-22 using a cradle rather than container. This article also has some interesting notes about the relative capabilities of the CMV-22B versus the old C-2. It seems the former can deliver appreciably more cargo at long range, with the advantage of being able to land direct on the 'phibs. Handy if your broken F-135 is on an LHA or LHD.....
http://navalaviationnews.navylive.do...s-golden-mile/
If a naval power only had VTOL capable fleet carriers the CMV-22B would seem to be a sensible option......