On a related note, it&#x27;s cheaper (per cartridge) to just buy from Dorco directly. I buy the Pace 4 cartridges in bulk.<p>It&#x27;s a solid product, at a great price, with excellent customer service. I recently had a package lost by USPS (they got confused because someone had forwarded mail to my address), and after a single email to Dorco, they sent out a replacement order (despite the fact that they had nothing to do with the original package getting lost).