I won't tell you which is best - they all have their pluses and minuses.
We fulltimed for 8 months with a truck and trailer. We have now been fulltiming for 3 months with a class A and towed. We move a lot - every three to five days. Having a MH and toad is easier - set up, breakdown, and on the road. But it is more expensive - gas, insurance.
When the weather is bad on the road we can pull over just about anywhere and have lunch and wait it out - without getting wet. I can make coffee or lunch while moving so it is ready if/when we stop. If we want to tour an area without staying there, we can park the rig, unhook the towed and go. Most of the added convenience is when one is on the road. But, we do now have a built in generator, built in inverter, and three methods of heat. Which all helps a lot.
When one is parked, a 5er of the same length probably feels more like home - no steering wheel, no driver's seat - it feels more permanent. But, that is really the only advantage I can see, that I experienced with a tt. Your mileage may vary...