Hi Scott,
Excellent review ! I have both the RS2E and the RTS400, and I love them both ! They are so smooth, and leave such a beautiful finish. I couldn't say a bad thing about them. I was using the RS2E to sand drywall, and it is way too heavy for an overhead application.
I use the RTS400 for sanding face frames, which I typically make 2 inches wide, and I use the RS2E to sand plywood panels and doors.
Thanks.
Brian