I'm refilling the 56, 57 and 58 cartridges for my 5550 and I used to fill 45
and 78's. I would agree with the 45x10 and 78x5 figures, but can't yet
comment on the 56,57 and 58 as I've only recently started refilling them,
but from other people's comments they can be refilled about 20 times I would
guess. We'll see. I'm not too bothered as long as I get more than 5 as my
usage isn't as great as some. Quality great so far as well.