Yeah, i know. But that's 200 for a "guaranteed working or money back" turbo vs a pumping station without any pics from a new seller in an untested state. Controllers are quite cheap on ebay as well, and you can use pretty much any cheap membrane pump that goes below 10 mbar.
And if either the blades scrape, the bearings are EOL or seized, the diaphragm is broken or the controller is toast the thing is pretty much a paperweight. Same if it's a contaminated from pumping questionable stuff. It's a "plug it in and you'll immediately see if it's working correctly" type of device and it's sold as completely untested without any pics...