You've got some great opinions from rotary lovers so far, so don't get mad at me guys, but I'm not in the same boat.
I have all of the popular detailing machines most people use: PC 7424, Cyclo, DeWalt rotary, and a Metabo. I even have a
UDM on the way, which should be here any day now.
I initially bought the DeWalt rotary, and had a lot of trouble using it, and just plain didn't care for it. I was told that the reason I was having negative results was because I was trying to use too large of a pad, and the DeWalt was too heavy, so I bought a Metabo, and used smaller pads.....same issues. I've watched every video I could find with tips on how to use the rotary, and used my two rotaries on several details. I have now become fairly good with the rotary (after a LOT of trial and error), and my final decision.....I don't like it.
I'm not in a rush, and I don't detail vehicles with extremely bad finishes. Most of my details are on fairly new vehicles that are kept up fairly well, and the rotary is overkill for me.
Even if I plan on doing a big polishing job, I would still rather grab my PC and/or Cyclo over the rotary any day.