Rim racks (holds by the rims) and tray systems both delt with the odd shaped bike problem. The NS Rack IMO (and I don't even own one) is my favorite.
Bike sway - if on a road little sway for roof mounted but possibly some for some of the hitch mounted types.
Off-road - both have issues. Hitch mounted extends your vehicle so even if (like the above mentioned) hitch racks raise your bikes higher than the vehicle your departure angle is going to be worse. Roof ones - well now we have major sway (my buddy has the cobra ones and going up the Vedder road when it use to be drivable for his van - the bikes would swing 30 degrees to either side - scary!)
Lifting is a pain but access to the rear is lost with hitch.
If you bent your reciever it means you were using the useless 1/1/4" reciever instead of the 2" receiver (you can put a 2" receiver even on a car though it might need to be custom made but it's worth it).
I've carried 4 bikes on a tray system - even off road (But it was easy offroad - far too long a vehicle with 4 bikes for anything other than bumpy dirt) and for long trips I have a modified hitch (not the receiver) to allow me to pull a trailer and have 3 bikes on my rimrack.
Finally - any system that has pivots for folding up or allowing access to the rear (this is for hitch systems) WILL droop over time. Recently I had most of my rim rack welded together to prevent the drooping (fatigue occurs at the pivot points). So although people want the folding features in the long run it will cause your rack to droop (thus I prefered the old NS rack to the new version which allows you to drop the rack down - heck it's almost as easy to remove the rack from the receiver as to fold it down to get access to the rear)
What to recommend? Depends. Two bikes - roof would be a good system assuming you don't plan to carry anything else on the roof at the same time (I carry a box and multiple ww kayaks at times). More than two bikes - go with a good hitch mount rack (NS rack is my choice, but other tray systems are good choices too). If you are using a hitch mount - make sure you have a 2" receiver (has a much greater tongue weight - the 1.25" are silly anyways)
