I think you'll be hard pressed to find someone that would put Vita/Maxx in the same league as Sundance or Hot Spring.
I looked at the Edison and Rhythm as options for myself. I liked the Edison a lot, the seats were more comfortable to me. I tried liking the Hot Springs, I didn't want another full foam tub and they have fluffy fibercore. I liked the dealer too, great guy, laid back, no salesman games. But I just didn't like the way they were shaped. But that's me... obviously other people love them. I would say pick the one you like and go for it. If that's the Edison, then all the better for save a few bucks. But if you like the Rhythm, I wouldn't let $800 change your mind... these things should last a lot longer than you'll ever worry about a few hundred bucks. (though the quotes I had for the two were only $300 apart, maybe the Hot Spring dealer has some wiggle room).