: I'm looking at buying a random orbit sander.
Richard,
BTW B&D and Dewalt are the same company. Dewalt has replaced B&D's "professional" line. If the B&D sander is a handful the Dewalt will probably be a more powerful and durable handful.

I have two Bosch ROS's a 4.5" light duty (3283DEVS) and a 6" heavy duty unit (1370DEVS). Both are variable speed, and I agree that this feature is wotth the $10 bucks or so it costs. This is particularly true when doing light sanding on a boat or you want to just lightly sand a surface. Both unit are two handers, but the front handle on the 4.5" folds up out of the way. This is nice in tight quarters.

The 4.5" has a triggered handle that emerges perpendicular to the axis of the motor at about halfway up the casing and the folding bar handle opposite. As the handles are low on the casing they make it easy to control. A palm sander is more likely to tip and gouge the work. However, if your work is higher than your naval, the palm design is better for your carpel tunnels as the wrist isn't flexed as much. If your work is at or below your waist the setup like the Bosch is better. Lastly, having the tigger switch handy is a real plus rather than searching for a slide switch somewhere.

The 6" is, like the B&D, based on an angle grinder. It's more agressive and vibrates more than the finish sander. Like a grinder the motor housing is one handle and there's a removable handle perpendicular to it which can be move from side to side if you're a lefty. The switch is easy to reach with your thumb if you're a righty, not if you're a lefty. I usually take the side handle off as I am more comfortable grasping the front of the gearbox housing with my left hand. It gives me better control and feel for the machine. Used in this way I've found this to be a nice tool for heavier sanding and big jobs. It has a "soft start" feature which is supposed to make it easier to control on starting, but I rarely have it in contact with the work when I fire it up,

When using either machine, I wear padded safety gloves to reduce the potential for vibration related injuries. They're available at Home Depot.
Be well,
Geo. C.