A power surge protector at the power pole is now a very wise tool to use.
I have for ten years used Walmart stinky slinky, replace every other year and works for me. However the attachments are another story. Screw on type connectors for both end of the stinky slinky are a good thing and a transparent connector at the RV dump connection is a good thing (monitor for a clean flow).
The honeywagon size should equal or exceed the size of the black tank and hieght is important, it need to fit under the connection(s). Regardless of the type of honeywagon always dump prior to a full tank (don't ask me why).
A handle grab for the screen door is a good thing for $10.00 (Amazon).
A set of "Dog-bone" electrical connectors for the power pole. 50amp to 30amp is primary. 50amp pole power breakers are better (less used), I have all 50amp to 30amp, 50amp to 20amp, and 30amp to 50amp.
A good lubricant for all valve stems, door hinges/locks is a good thing
And don't forget to grease the axel bearings. I do mine twice a year and recommend to everyone to do it after taking delivery.
PS Keep those questions coming....