This sander really does work fine, it does the job it is designed to do. I do have a couple of complaints though. Firstly the dust bag is basically useless. Mine has broken twice and when it is in place it is largely ineffective. ( Actually though, I fail to see how a ssnder's dust bag can work without a vacuum, but anyway)  and the other gripe is the power switch. Mine is in a dust protective booted cover, that I usually fail to properly toggle, so when I start to sand, it will turn off - or the worse case it turns back on when I am setting it down.  I can say however, that this unit has held up through the years that I have owned it, dropped it, loaned it . . . So I have no question as to its durability.  I cannot base it on any comparisons with other RO sanders, but I can say I have got my moneys worth over and over.