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There is not hard fast rule about 08 product. Some makers may make bigger changes than others, some may introduce a new model while also dropping perhaps another. Some will make small minor changes. I can tell you as a dealer that each year there are changes that we like and some we don't. After just getting back from the Aqua show which was smaller than normal, there did not appear to be a lot of "Big" changes D-1 did do some cool stuff with cabinets, they make a very fine product but you will pay top dollar for it. Some interesting spas out of china were there. they appeared to be very nice but not enough savings to make them make sense.
I checked with my Caldera salesperson, he says the one I have been looking at is a 2008. The waterfall changed from the filter to its own spot on the back of the tub. I do notice that on their older (nicer) brochure, it is a little different (unless that is the newer one and the guy is lying through his teeth?).Anyone out there with a Niagra for a while care to chime in on where your waterfall comes from?