Done it both ways
Over the years we have towed both ways- 4 down and most recently on a dolly.
Hands down we prefer the dolly (American Car Dolly).
When we towed 4 down with our older rig years ago and we seemed to constantly struggle with hooking up and constraints. On one occasion when up in the Maritimes of Canada we had just come down a hill (pre rear camera days). I heard a grinding noise and asked the Mrs. (Momma) to go to the back window in the MH and see what the noise was. She was grumpy and grippey but reluctantly she went to look out the rear window of the rig. Next I heard a blood curdling scream from the rear and I looked to my left rear mirror and saw the Jeep toad pull out to as if it wanted to pass the MH!!! It was operator error and yours truly had not properly installed the hitch. And with a blessing the safety cables barely held it until I could coast to a stop. Made it home safely than goodness.
For us now with the new rig and Momma insisting on a front wheel drive car, the tow dolly is easy and quick and we have numerous safety features (spare dolly tire, car to dolly chains,break away switch, electric brakes, safety chains to tow vehicle). Last trip the total load and hook up was 10 minutes--- and it tows beautifully with no apparent adverse impact on mileage.
All of us have on the forum have likely had many different experiences with toads. Having done it both ways I plan to stick with the dolly.