Do you think this is something that people would actually buy and use if it were available in their LHBS?
Honestly for me it would be all about the price. If it wasn't priced much more than, let's say a better bottle, 30-35 bucks or less I'd be all in. (Not counting the outside bucket, which we all probably already have lying around, if we didn't want one with a drain at the bottom.)
Personally as much as I like shiny new toys, or interesting fermenters, I opt for buckets, or sometimes better bottles, simply because of the price. As much as I'd like a fast fermenter, I can't see spending the equivalent of 7-8 buckets for it. (Or that much in ingredients.)
BUT, personally I like this setup.
Especially if it was adaptable, like I COULD add a drain at the bottom if I wanted to, but I could use it without if I didn't want to pay extra.
(Like maybe if the bottom of the conical part came threaded and capped with some standard sized plastic thread, that I could either buy a pre-made valve setup from the manufacturer, or I could go to a hardware store and built something that suits my needs.)
I love the idea of a dirt cheap way of temp control using something existing like a fermenter bucket. Not just with cold water as a swamp cooler, but also I bet I could come up with a way to keep a fermentation warm in a cold room or closet.