I always wanted a belt sander but never had an actual need until I started a shop workbench consisting of a 2x4 laminated top.  Once everything was glued and dried, I pulled her out of the box, attached the dust bag and adjusted the belt tracking on medium course sanding belt and let it rip on high speed.  I was pleased at what quick work the sander made of smoothing the laminated top.  Only light pressure was required for the sander to do its work.  The sander fit comfortably in my hands with very little vibration.  The dust bag was able to capture some of the dust being generated but just as much went airborne.  I guess this is to be expected with any belt sander though.  The variable speed came into play when I need to smooth some uneven edges on the cabinet carcass.  By dialing the unit down to a medium-low setting I was able to control the amount of material being removed safely.  Keep your eye on the electrical cord as I found out the hard way it can be grabbed by the belt and yanked up into the sander.