Replying to Hydrofoil: Air Chair, Sky Ski etc.

I want to buy an air chair or a sky ski and was wondering if anyone on NS has any suggestions of where to pick one up. I am on a little bit of a budget in that I don't want to spend more than 2 grand but I would prefer to spend the least amount possible.

I found this one on Ebay which looks like it is from the skyski store. It has the billet wing design.

http://cgi.ebay.com/NEW-Sky-Ski-Hydroflite-w-polished-bi-wing-billet-foil-/350021754500?cmd=ViewItem&pt=LH_DefaultDomain_0&hash=item517eec1e84

So I was wondering:
1) Where is the best place to get one.
2) Will I out grow the billet wing design quickly and how much will it cost to upgrade.
3) I have ridden one a few times and I think it is tight as shit, is there a risk of really fucking yourself up?
4) Does a tower make a big difference.

Thanks

And here is a video of a guy sky skiing.