This rig is becoming increasingly popular for both winterizing ease and it also offers an added emergency safety feature. With a 3-way valve, one only need hook up a section of hose and leave it lying in the bilge. When ready to winterize, put the hose in a pail of antifreeze, turn the valve to the second position and run your engine. Turning the valve to the second position will close off the thru-hull intake path. After you're done, turn the valve back to the first position and you're all set for Summer.
The added emergency safety feature with this set up is that the 3-way valve and the hose lying in the bilge would come in handy if you had a major hull breach. In such a case, again, turn the valve and run your engine. The engine will act as a huge bilge pump when your true bilge pumps would have no chance of keeping up. All the while, you're engines are running and you're heading back to port while pumping.
I'm installing strainers in my 3807 so I don't need this setup for winterizing but the plan is to replace the hoses and install 3-way valves as an added safety feature. I've seen some pretty bad impacts that have caused both hull breaches and shafts pulled right out so this simple system is worth it IMO.