What do you prefer? I have always been taught to use Crawfords working for my previous employer for years, now i've been out on my own for a year I'm not sure. I just did a 4700 square ft. custom, with just myself and a helper and I had trouble sanding even with the medium blocks. I think I might have had troble because the time some of it sat on the trim before sanding. It slowed me down alot and though no one else noticed, I wasn't satisfied personally with the sanding. It wasnt perfect. I need something that sands a little easier and completely clean but wont leave a pit. Does anyone use the lightweight from Sherwin? It seemed to be good. I also tried DAP fast n final and didn't like it. I don't think it is made to dry sand much. HELP, I need an experienced opinion to get my nail hole prep perfected.