I bought this to use on a brand new IP4950 printer for printing full colour covers for DVD cases and also printing directly onto DVDs for my videography business. My printer had never used any other ink except this CISS system and it has worked perfectly for more than a month now. I opted to pay the extra $25 to get Rihac to supply and install the chips on the cartridges, to save having to fiddle around with it, plus since I had not used a set of Canon ink cartriges yet I did not have the chips to use.

The instructions that come with the unit, say that the chips supplied by Rihac are self resetting, so that you do not need to follow the ink monitor disabling protocol that is also listed in the instructions, but this is not true. The printer stopped printing when it thought it had run out of ink and the chips did not self reset. When I followed the protocol for disabling the ink monitoring on the printer (which can only be done once each cartridge has used approximately the amount of mink that would be in a normal cartridge) the printer continued printing with no problem and has been ever since. Since the CISS ink tanks are outside the printer you can easily see how much ink is left anyway so monitoring is not necessary.

The other glitch I found was that since the CISS ink tanks sit outside the printer, you need to have the cover of the printer raised slightly to allow the ink tubes to get to the print cartridges inside the machine. There is normally a process on the underside of the cover that tells the printer when the lid is shut. When the lid is open, as it has to be for the tubes to get to the tank, the printer won't run. The instructions tell you to put the spare ink tank plug into the hole that the process normally goes into, but I found that the plug did not go deep enough and so my printer still would not run. I just wadded up some tissue and stuffed it in the hole and then the printer worked fine. I am planning on cutting out a small hole for the tubing to exit from the inside of the machine with a dremel rotary tool so that I can have the lid shut properly but I haven't got to this yet.

I have previously printed DVD labels and covers in house using offical cartridges before and it cost a fortune since the covers especally require full coverage of ink at full photographic resolution. So this system is literally saving me a fortune in ink costs. To put it in another way my printer cost $109, one set of ink cartridges if I was using the official canon cartridges would cost $110, so I have already saved the cost of the printer in only one set of inks and the CISS system comes prefilled with 100mL of each colour (ie around 10 cartridges worth of ink).

I haven't used up the initial supply of ink yet so I haven't needed to refil but since the ink is continuously fed from the external tanks you can refil the tanks with out the mess of removing and refilling cartridges. So not only is it cheaper to use a CISS system but it is much easier to refil you system with ink.

For those of you worried about clogging up your printer and voiding your manufacturers warranty there are several points to keep in mind:

Firstly printers are so cheap these days the amount you will save ink costs before your printer is clogged up will pay for a new printer many times over. As I said above I have already used more than a single set of inks and my printer is already paid for by the money I saved.

Secondly, your manufacturers warranty only lasts for a year, so if you like you could use official inks for that first year, then once your warranty runs out you can switch to the CISS without having to worry about voiding your no longer existant warranty (though as described above you will have spent more than your printer is worth in ink replacement costs)

Thirdly the pint heads are easily removable form your machine these days and are therefore easily replaced if they do clog up.

Lastly these inks are filtered with a 0.1micron filter. To put that in persective in research science we often need to sterilise liquids without heating them, the easiest way of doing that is by passing the liquid through a 0.2micron filter. 0.2 microns is small enough to filter out all bacteria. This ink is passed through an even finer filter than this. Only molecules in solution can get through this fine degree of filtration, so it is highly unlikely that there are any solids remaining in these inks to clog up your print heads.