I have have some problem with my unit . first , though , the good side ... I have be use this since July , 2006 , which have give I enough experience with the machine to write a credible review . the unit be powerful , without be unmanageable . it be light enough to be able to use on vertical surface and run relatively cool and quietly ... although I find that a set of noise cancel headphone help tremendously to reduce the racket . it also be design with a nice flat top , so the sander can be turn upside down and use to -lrb- carefully ! -rrb- hand sand small part and sharpen some tool . now , the not so good stuff ... the tracking control on my unit have to be adjust all the way over to one side to prevent the belt from work it be way off the two pulley . even at that point , where the knob can not turn any more , the belt run at a ~ 5 degree angle to the chassis . the graphite wear pad do indeed wear . quickly . I go through one for every five or six belt . this may be normal or due to the mistracking ... I would be in a better position to evaluate if I have one that track correctly for comparison . I have have problem with sand dust plug the inside of the sander ; once to the point that I have to completely dissemble it to clean it out . the optional Bosch exhaust hose -lrb- vac001 -rrb- that connect the sander to a Shop-Vac be make out of very thin ridged plastic and do not pass enough air through it to keep the Shop-Vac 's motor from rev up and whining . active exhaust certainly help clear the sand dust , but , without sufficient cool air , I be concerned about the impact on my Shop-Vac 's motor life . all in all , I be rating this sander as three star . I would be happier if the local Bosch repair shop tell I that the tracking be abnormal , but they say that it be ok ...