I've got an Oberdorfer and frankly that thing can take a beating. It's got a 4 foot hose for sucking or filling and then a manifold with a quick connect so I can drain or fill the genset, the gears or the mains. Not sure why you'd want the long hose (for the dock- I know some boats that do it that way but it's a two man job; one person sits next to the dock buckets and yells when they are close to full) unless you have a remote wireless switch on the pump- how can you stand next to the buckets to know if they are full? Walking the final 20 steps from the dock to the engine room is not a hassle. I get extra buckets from my local DD repair shop- they have hundreds of empties. I empty both mains- at least 7 buckets- then fill both mains. The marina takes the used oil for a small fee.
One of the things I have noticed, Nobody really wants the empty 5 gal pails. I have a deal with a local shop to pour the oil out but he does not want the pails either. Yes, they are recycling plastic, but nobody is comfortable with ANY remaining oil in them. When I gather to many, I take them to the city haz-mat disposal site. They love them.
I usually let them drain really good and clean them with degreaser and then give the 5 gallon buckets away....as buckets people seem to love to take them, with the lid on nobody wants them, go figure.
I used a 32v Orberdorfer on my old Hatt and it worked like a champ. I used to put the pails of new oil on top of the engines the night before and turn on the block heaters if they weren't already. Put them back on after starting or running the engines. New went in just as fast as old went out... When we were cruising full time I was doing about 4 changes a year, so the little things added up.
Your a nicer guy than I. This takes time and responsibility. The de-greaser and wash discharge has to go somewhere....
Well it's 20 steps times 8 or 9 pails... At 50lbs each or so .depends on the boat and how roomy the ER is... When I got on the boat 8 years ago, it took me 10 minutes to run a couple of wires zip tied to the long hose, with a switch at one end and just tap in teh wiring near the pump. Well worth it, As everything else it depends where you are,,, I ve always had issue getting auto part store to accept the used oil and many marinas don't have used oil collection.