, Brian, Ive used Klingspor for the last twenty years or so and I really think the red disks are the best, the heavy weight and most expensive ones....Ive been using a Fein 6 inch sander and start sanding redwood with 120 and end with 320, the same with epoxy, I use a vacuum on the sander and a blow gun to really keep the sanding pad clean, the disks last forever this way and can sand the whole kayak with one of each of the disks. If you really want an experience, try the 8 inch Fein sander, unbelievable, I hope this is a good Christmas...... David Barrett