I would really check to see how far it will swing versus your rear doors. A link in one of the posts claims a 600 lb swing away capacity and that you can swing it out of your way 360 degrees.
Realistically it will swing perhaps in the neighborhood of 90 degrees, depending on the pivot point position inside, at or beyond the end of the rear bumper. Depending on how far it actually swings with a cargo box or other items on the platform will let you know how much if any interference there will be with the max swing you can now achieve with the rear doors.
As for the 600 lb claim. Hmm. Maybe when the thing is not swung out and is latched. I haven't seen how it is constructed but heavier duty models utilizing spindle-type hinges spec about half that weight when latched. Any weight extended out as the carrier arm pivots outward lowers the realistic weight capability quickly, depending on the mount, pivot "hinge" and the pivoting arm construction.
I think I just read your estimating about 100 pounds so even a Harbor Freight version if they have one, should handle that. This is one of those things that might require some good research before you buy. Makes a case for brick and mortar store shopping versus buying off the Internet. Hopefully you have found good information and what you buy works out well for you. Oh, and for some other potential buyers with Class B motorhomes, if you have rear facing waste system gate valves or things like auxiliary propane ports, etc, some of the swing hitch systems will partially or completely block those.