Yes I understand the feeling fully. The wife and I flew up to Oregon to buy our bus. It really did not set in until we were fueling it up at a truck stop. Money was exchanged and we had our bus.
It will be a great feeling.
I'd imagine your bus would drive similarly to a big u haul. Probably even better once you get the hang of it. Have you driven a truck with air brakes? Air brakes take a little to get adjusted to but once you drive it you'll be fine.
Just drive slow to start. No need to get on the freeway and try to run 65. Keep it around 55 and work into it. My guess is 55 ish will be its sweet spot anyways. Just let traffic roll on by. They'll get over it.
Good luck, have fun and take some pictures for us.