If you want long lasting belts, get emery cloth belts. They will out last paper belts 10 to one since they are tough fabric bands not paper so you can sand an edge without worrying about the paper band tearing if it catches a bad spot.
Machines are great - for large areas. I'll probably use a multitool for the chestplate and helm... but the other areas are all going to be hand-sanded. I have never found a machine yet that does a better job than I could do myself.