I met a guy that had a f150 4x4 front end under his e150 with swayaways and he flogs the daylights out of that van. I am not a fan of those front ends because maintaining them is a pain. If you do not mind regularly going through the front end to keep it in good shape they are not a bad choice. The up side is less unsprung weight and better ride. The down side is strength. Another thing to consider is if you just want 4x4 to pull your boat up a ramp or go up your driveway in the snow or some easy task like that then ttb would not be a bad choice.