Reading a lot here and it seems that most people refill their carts a few times before tossing them. I'm using a KR808D-1 as well but I'm not sure I want to get into the whole refilling thing. Is it a big pain to do? I know it will save money in the long run, but is it not easier to just buy carts? FWIW I get about 2 days out of a cart as it stands now.