I have been using cheap sandpaper from Harbor Freight, both the emory and the aluminum oxide. I've really been burning through the stuff, and the grit seems to wear off easily. Sick and tired of that, I bought some Norton today. I got the 3x in 220 and the SandWet in 400 and 600. OH MY GOODNESS! It cut well both dry and wet, and the grit didn't wear off. In fact, I could dust off/unclog the paper and keep going. I'm sure most of you guys are past the cheap sandpaper stage, but if you're not, it's totally worth it to upgrade, IMO. Anyone care to share their preferred brand?