No one has responded but I assume preference is hard piping with glued or threaded fittings.
Banded fittings can leak, but like I say they are used in construction. On cast iron pipe.
Usually this type of piping is filled and tested with some head pressure. The tests sometimes fail.
Banded fittings are used on cars all the time (radiators?). They do work. On cars probably used due to vibration.
I think the pipework for return lines where there is some pump pressure is better screwed using PTFE tape or glued. A gravity drain line, I wouldn't have thought, would be as critical. I believe those flexible pipes are made from EPDM rubber. As long as the correct diameter pipe is used with them I don't see a real problem. Once tightened, the internal surface of the flexible pipe will form a very secure seal against the exterior of a rigid pipe, i'd have thought.
Here is a typical no hub coupler. They come in many sizes. The thin metal casing helps make it rigid.
Fernco's don't have the metal casing. It's not a robust fitting and I would never use it for waste piping in a stud cavity. Maybe underground, maybe. Where the pipe would not move. This all comes from the construction company/code aspect. Flooding in homes is a big deal (damage). A broken radiator hose not so much.