I know there are many printers out there that have printed on blank coasters. So, my question is what is typically the “standard” or most used size/shape? what weight?-light, medium, or heavy? Or what do you lady printers out there recommend? I have the source for 3.5″ or 4″ square or round blank coasters. Thank you thank you! 🙂 (wasn’t sure what was the right category to put this under…….)