I know there have been many prior opinions stated on this and other sites related to this issue. My thoughts on expired carts are this...
I believe Epson most likely
has a very valid reason for placing expiration dates on the carts in relation to when they were manufactured, and subsequently recommending that they be used up within 6 months of opening and placed into use.
Many have stated it's pure hogwash and only an attempt to sell more ink. Some are also proponents of trying to outsmart their machines to skirt around the need for cleaning cycles. I think this becomes a game of Russian Roulette -a gamble. I do not believe for one minute that Epson has designed a flawed product, as some would like us to think.They are selling way too many of these newly headed
machines over the past 4 years and have way too much at stake. It is very unfortunate that some , such as yourself, wound up with a problematic model, and I can surely understand the frustration of your experience.
It seems to me after 2 1/2 years at this WF printing thing now and reading many horror stories posted on the net, that some machines are more prone to problems than others, and there are many factors
, from actual build quality,site location, to amount of usage, that can contribute to ink related problems.
I have said a few times that my problems
seem to be directly related to 1% low carts and thankfully I have been able to recover every time I've had an issue. I have never done a power clean to resolve a dropout or clog.
Now for the meat...
Ever since I purchased my 9890 slightly over a year ago, my 7900, now 2 1/2 years old, has had a smaller workload. I do make it a habit of switching PK/MK duties on both machines to make sure that those channels in each are kept somewhat active.I print on each at least once a week but usually not big runs.I do not remove my carts to shake them,or perform any other rituals to the machine such as running in service mode.I changed the wiper on the 7900 (which wasn't really that bad), after getting paranoid when Erics thread started last year, and am about to pull the wipers on both machines and clean them this week to see just how bad they are.
I had a Cyan problem on the 7900 last week where the channel dropped out completely after a PK to MK switch (which was more than likely due to a pressurization thing) ,and while switching out the Cyan carts I noticed that a few of my carts in the 7900 are now over a year past date, but not far over 8 months of opening them and placing them in the machine.They are the 350ml that I used to buy to save a little $$. I would never buy 700ml carts unless I was printing a lot, on a daily basis.
I hope I dont jinx myself buy posting this, but so far I personally have not experienced any problems.(knocks on wood)
I might mention, that I pat my machines, praise them, and kiss them every time I switch them on.