I do mostly wood but this is a good one - Bosch.

I've had the 'turbo'/standard orbit mode on a Festool - great feature. The turbo mode changes it to a straight rotation and will remove material very fast. The standard random orbit mode on these more powerful sanders is fantastic and fast though compared to the palm sanders. The bigger, two hands, 6" types are the way to go if you're sanding alot of area.

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