Well its a good price indeed, no shipping included tho, your link says 8 pounds postage.
Besides that, it they´re going that low is simply because they payed kickstarter price, much lower than the retail one.
That means they have units from the first batches stocked, and that one is the last of it.
First batches of mescalines are well-known for arriving smashed, crushed or with circuitry parts simply ripped off.
So you can go and save yourself 20 bucks, but you might be unlucky and receive one unit with damaged boards, having to contact folktek to get boards replaced, ship the old ones, wait for the new ones, etc…
And after all that, you still have to work out a power solution, the original adapter is terrible with a terribly short cable, can power only one board and you cant switch the unit off unless you unplug it.
Im selling a calibrated, tested and ready-to-use unit, 20 bucks more expensive.
Life is made of choices.