I've had them all, 3 TC's, a MH, TT, and now my 5er.
We have 3 slides, one for the bed and 2 opposing 14'ers in the living/kitchen area. It almost looks like a ballroom in the middle. Ours is only 31 foot in total length. It's called a 29.5 model someone said they measure from the inside rear wall to the inside front wall go figure. I've had no problem putting any where I want it. Here at home I have 4 flags to back it between as I only have 3" clearance on each side to be able to open the slides. The main thing is to have good mirrors. I love being able to adjust them electrically.
I don't have any road side assistance. I will do my own work anyway and if I can't handle it there's always the plastic.
Alaska, went 2 years ago. A fiver is no problem. You'll need to study for the trip mainly for all the things you'll want to pack into seeing and doing. This site has a LOT of info. I bought a popup TC just for this one trip. It was damaged and I fixed it, we put 13,000 miles on the trip. 2 people in Alaska wanted to buy it. I also had a TT at the time. Now that I've been there, I would take the 5er. I would make sure I had good tires, a spare, one set of bearings and a grease seal. Not because of the roads but just because there's a lot of space between help.
These are my opinions and not that of the staff and management, but what do they know.