Digital BW, The Print

Hi,

Can anyone venture a guess as to what is a 'reasonable' life span/# 
of refills for Epson-mfg. ink cartridges for the 1270?

I refilled a color cartridge for the third time yesterday -- it was 
much harder to suck out all the foam, and the chambers only took 5--
6cc's of ink before it started coming out the top air vents, instead 
of the 'normal' 7.5--8. This was consistent across all colors, and 
there was still nik present in the vents (which I blotted up with 
paper towelling) for hours after the refill. Presumably I should be 
very concerned about this cartridge running dry well before the 
droplet-counting chip warns the ink is getting 'low'. 

This particular cartridge is over a year old (it's the one that came 
with the printer). I have refilled it with the MIS, non-archival 
color inks.