I have had the Sewer Solution for three years and love it. The initial problem I had was with the connection. The Airstream had the Thetford bayonet connection and it was too large for the SS. I went through 3 adapters all of which failed because they are made of flimsy plastic and the ears would break off. I finally did the intelligent thing and bought a standard bayonet, sawed off the Thetford connector and glued the standard connector on. It works great.
I do not see the wisdom of not using the water hose for the whole dumping process. It forces a thin stream of water into the ouput hose and acts as a mercerator. It also keeps any fluid from contaminating the quick connect point.
One of the great things about the SS is that that highspeed stream of water can be pointed up into the discharge tube and cleans it and the sliding valve. In fact it forces water into the tank which flows back out when the stream is redirected out the hose. You can see a lot of stuff flowing out that would have been left by not performing this one little task.
By letting the water run for a few seconds after the tanks are empty flushes the hose and keeps things relatively sanitary. One does not get ones hands dirty and there is no odor to contend with.
I bought the 10 foot extension hose and have not had a case where I could not reach the ground dump. There have been cases where, without the extension, that would have happened.
I have never been to a dump station that doesn't have a water supply so I have not encountered that problem.
All in all, it is a sound investment. My only complaint is that the output hose is very tough and when coiled resists being forced into the hose compartment in the rear bumper. I reminds me a little of trying get an unruly child into the bedroom with arms and legs splayed out catching on everything in sight.