We find the side door on our Northstar 12' STC really convenient.
1. Stays much cleaner.
2. Makes getting into camper when on the side of the highway much safer.
3. When parking we just make sure there is space to open the door/steps.
4. A side entrance will obviously make your camper overhang much more, but we can usually back into a parking spot, overhanging grass, etc. and cut our footprint to fit regular length.
5. Our 3 or 4 steps fold up so tightly we can lower the camper almost to the ground when off the truck. We don't have a basement so we don't have such a high climb up.
6. I'm not sure which wardrobe I might have "lost", but we have soooo much cabinetry inside that we have never lacked storage.
7. Towing obviously requires more hardware with overhang.
We have never owned a rear door, so can't really compare.