Tow flat or with dolly?

There is no better, just differences. You only choice seems to be a dolly. A dolly adds weight, storage considerations, longer hookup/unhook and cost less. The vehicle must be able to tow with the rear wheels on the ground. The dolly can tow vehicles that can't be flat towed and adds flexibility on towing different vehicles.

Be sure your dolly has brakes.

I flat tow and never regretted that decision.