donandlin,
I am interested in what you learn. We are planning our first trip to this area in May. I used RVTripWizard to find a camping location (Archview RV) that is close to the Arches and also Canyonland. We plan on packing up camp and making a day trip to the Delicate Arch viewpoint and the next day to "Dead Horse Point".
However if there are other campgrounds suitable for a larger Class A I am interested in knowing more. The TripWizard shows the BLM campgrounds you mention. I wasn't sure how "Class A friendly" they are though.
Based on our trip duration we have 2 days to spend in this area, and then we return back north. Next year I'd like to extend this trip to Southern Utah and the grand Canyon.
I'd like to hear tips other people may have. We are new to RV travel - it's our first year.