I've got one for my bedroom. And yes, it does have a big hose (similar to one you would use on a clothes dryer) to vent the heat out the window.
It does the job nicely for one room, although I would have expected better performance from a 10,000 BTU model. I don't find mine any noisier than a regular window unit.
The upside is that when the weather turns back to comfortable, I can remove the hose instantly to get fresh air from outside. It's a far less permanent installation.