We tow 4-down because we can. Looking for new vehicles, we try to find towable ones. It's easier for us than many, because we like manual transmissions anyway.
Lately, this Forum has had a couple inquiries about flat towing RWD automatic vehicles. Unless that automatic IS towable (which would make the vehicle a candidate for 4-down), Dolly should NOT be considered as an option.
NOBODY recommends backing a vehicle onto a dolly and towing it backwards. Vehicle manufacturers don't, and Dolly manufacturers don't. Why? Well...
1. Motor Vehicle Steering is designed primarily to go Forward. Its design makes it want to go forward.
2. Steering Wheel Lock (or some other kind of tiedown) is inadequate for going backwards because the steering is built to go forwards. If anything from the steering wheel all the way to the wheels comes loose, the wheels will immediately go to full hard over, all the way to the stops, left or right. That can't be good a 65MPH
3. This isn't mentioned much, but thinking about this, the front end of most vehicles is the heavy end. FWD cars are really that way, but RWD cars are still front-heavy. You want the bulk of the weight on the dolly axle, not wagging around behind.