I have a Kestrel Das6 dual action. First used it on my S2000 which was soft paint. The car was basically faded to pink on some panels and I'd negotiated some money off for a respray. However, after some advice invested the money in the polisher and all the kit. It came up bright red, removing all the swirls and all minor scratches. Looked awesome.
I then used it on my Z4M over the winter. The Interlagos paint was almost matt in colour, now you can clearly see the metalic flake and most swirls\scratches have gone. However, I'll warn you now, it took over 20 hours to do start to finish!!
Dual Actions are fairly safe as long as you start with the least aggressive polish\compounds and pads.
Very satisfying!!!