I've had good results with Meguiar's scratch X and also Harley Davidson's scratch and swirl remover. Wizard's products are also a favorite. I hate to hear I've been wasting my time waxing cars by hand all these years having never owned a power buffer.
The young man that bought my last one seemed rather impressed with the way the paint had held up on a nine year old truck. He bought it to celebrate his 81st birthday.
wax and polish are completely different things.
doesnt matter how you apply wax, by hand, oribital... however you prefer, the results will be the same. its not an abrasive, it just offers paint protection and a nice shine, not paint correction
as a polish is meant for.
a polish needs to be worked into the paint, and broken down by heat created from the friction, as it "smoothes" out your swirl marks and scratches. this is impossible to duplicate when you apply it by hand.
there are 2 types of polishes, non abrasive and abrasive. the non abrasive just act as a "filler" and fill in scratches, where the abrasives remove them.