Just purchased a Down East Windsor STS from a company out of Kitchener, ON at one of the home shows we went to on Thanksgiving Day.
While we did not plan on buying one until the next year when we are to start construction on a new deck, the price was reduced quite a bit so we bought a floor model.

I quickly removed top soil and put down compacated gravel with 2'x2' patio stones over top. If I knew for sure this spot would be permanent I would have poured a concrete slab, as leveling the stones was something else.

So far we have had no problems, other than a few missing parts such as sterio cabinet locks, and a tv remote.
When looking at the manual we thought our model came with a universal "Dolphin remote", and checked with the distributer and manufacturer, and it does not. So we have to get out of the tub to pause or stop the dvd, or cd. We can operate the tv though...

As this is our first hot tub, we didn't really know what to look for, but now we kind of wish we had purchased one with foot jets, and an extra (second) "master blaster" (extra jets in that seat).
We purchased a set of matching stairs, that you think would have came with it.

I've been told that we have to be extra carefull with the tv when it gets really cold here, and try not to splash water on it due to freezing damage.

I am looking into getting a cover lifter right now, as the kids need me to help open and close the cover; which actually might be a good thing.

I'm also toying with the idea of putting radiant heat pipes under the deck around the hot tub (and maybe under in a slab), to melt any snow build up. But it never snows in Toronto - LOL.