I won't flame because I don't know anything about Mitsubishis, but I think that you are bound to get a biased answer if you ask here. Frank brings up a good point about seeing them on the trail and aftermarket support.

What exactly are you planning on using this vehicle for? If it is just to tow a boat I wouldn't recommend either of your picks! If you want to do mild wheeling than either would probably work, maybe the edge to the Mitsubishi since you are more familiar with them. I think that they 4Runner has more potential though if you want to modify it.