Once you try these Japanese made sanding rolls, you just might toss out all your older style cartridge rolls, even though these are a lot most costly. Permanently mounted, they run smoother, without bumping or vibration. High quality abrasive paper leaves a more uniform finish than cheaper sanding rolls. They cut faster, work better, and are well worth the cost. For me, about the only real competition these have are Kate Wolf's split drum sanding drums, which you use with your choice of abrasive. Those are very versatile for use with whatever precision abrasive you wish, such as various 3M products. But these drums, once you use them, they'll become your standard tools.