I think the misunderstanding is arising from runnng without a pause, and continuously. if people do this it will only run for a month, before the head "wears". if someone was to use it as you suggested in your literature for a CaRx, how long would you expect it to last "running continuously" ? A month... not good enough I'm afraid.I still think that it is correct to claim "continues run" in this context, even when the pump head has "only" a lifetime of 800h.
"Continues" means here that it is allowed to run the pump/motor without a pause without risking to damage through overheating (leave the 800h as limiting factor aside here). Many dosing pumps have a max. duty cycle, e.g. 15 minutes on, 15 minutes off.
800h = 48000 min -> 16800 liters (4400gal) is a lot for a dosing pump. We are not talking about a return pump here.
Price point for the replacement pump head: $29.90