I use a 700 varikennel at home and have a 42" suv crate for travel along with a 42" nos to nos mesh crate. My boy fits in a 500 varikennel ok, but I don't feel comfortable leaving him in one for more than just a few short hours occasionally.
Right now I am at the national and have a 500 varikennel in my hotel room for the few times I leave him here. I also have the 42" mesh set up in the show area. The 700 is bigger than I want to travel with!