Hey Paul, being in the industry a long time and seeing good and bad results, if it was me, I wouldn't do it.
Seriously, the ink saving is so minimal when you break it down. The amount of ink you use per square metre is minimal. For the sake of a few cents/ml literally, it is not worth the trouble and expense it COULD cause with heads/lines etc not to mention down time and the possibility of losing a customer... or 2.
I am a Roland user now and for me, I'll always stick to the OEM ink as I know I will always have consistent results and the manufacturers backing.