There is a big difference in quality of rubber bands. Those you can get from the stationary supply are usually not very good. One of the better brands is SIG and they make a great deal of different sized ones. As to reusing them, I see nothing wrong with that as long as you check each one before you reuse it again to make sure it is not cracked or weakened in some manner. I store them in a light proof (ultra violet deteriorates them) container with either kitty litter or corn starch to absorb any fuel/oil residue that may be on them.