Epi weights

Anyone here have experience with EPIs weights? I have used there springs for everything but want to build a collection of weights for different riding. Was hiking about just ordering a bunch of weights from them or is there a better option.

Want more 18gram for future mods to other bikes and down to 16 and up to 21 and maybe higher just to have in the shop.
Looking for cost effective route as well as good quality any ideas?