Well. My CISS pack has finally decided to run out of black ink. I use it domestically and on checking back found it has been on the printer for nearly 4 years! Great savings and always consistent results. Sitting for a while the tubes sometimes seem to collect air pockets but that soon clears and printing continues.
Now they have refill bottles available. Even better as the colours still have quite a bit left. I haven't printed many photos but there have been some and its never a concern as there is always plenty of ink available.
A great investment.