I just bought a Rigid RO sander to replace my aging B&D that I have to keep buying replacement stick on pads for (and the shaft may be bent, as the pad wobbles). For stain projects, I always finish sanding by hand with very fine paper. For painting my TTT, I finished with the ROS using 220 disks.
I have a book somewhere in my collection on Router Basics. They have lots of unique ways to use a router, but I don't think I've ever read it all the way through. My two 15+ year old Sears routers still get used. I used one for cutting my sides from a template I made, and one is in a table that I also made, using one of the routers to make rabbit cuts in the edges of the opening for the lexan base to fit into and the slots for the T-rails for the miter and the sliding fence.