Okay, that's a very specific review. I own and use both the 9920 and 9924. Both are great grinders and for some reason we carpenters prefer the 3x24 for reasons of our own. If I had to choose, I would choose the 9920 over this model. The 9924 Dust Bag is a bit dated, and not in a good way. I like it because the pocket on the right side is right-handed, but it doesn't detach easily. The entire grinder must be taken to the bin and disposed of through the slot in the bag. Also, it has a rectangular port so dust cannot be picked up with a vacuum cleaner. The shoe or platen is also 4" - I think so you can control the left or right guide of the belt depending on the sanding situation. It doesn't bother me but it's there. This is an older model - a little more metal and less plastic. It's reminiscent of old worm grinders for cable hauling. As a result, it has a loyal following. But at the end of the day, I'd give the 9920 a close look.