Compatible ink cartridges: cheap inferior substitutes or genuine bargain? Original cartridges: over-priced necessity or high quality ink? How is anyone to decide when the data available is so scanty and inconsistent? Cut through the hyperbole and hype and check out these five points to help you decide which ink is right for your personally.

1. What do you print?

a. Mostly text

b. Mostly photos

Independent tests show that black compatible inks consistently give comparable results against OEM (original equipment manufacturer) cartridges.

If you want top quality photo prints however, you may need a genuine cartridge with matching paper. The big brands perform rigorous tests to ensure their own inks and papers get optimum results together.

However, an extensive test run by an independent review site* showed that prints from compatible cartridges got more thumbs up than the originals. Results were cross-referenced on various OEM and 3rd party papers on a number of different printers.

The conclusion: if results matter most, experiment until you get your best results. Experimenting not an option? Good results can be got from OEM inks plus matched paper. Alternatively, top brand compatibles are out there that perform lab tests on their own ink and paper.

2. How much printing do you do?

a. A little

b. A lot

The choice often boils down to money. A cheap compatible is tempting when you print large amounts.

But beware: not all compatibles are equal. The cheapest option can be cheap for a reason - poor quality inks, substandard plastic casing (affecting ink during storage or allowing leaks) plus many cheap compatible inks dry out too quickly or clog print heads.

You can buy cleaning cartridges to 'wash out' print heads or use the cleaning program on your printer, but the first costs money and the second wastes ink. A lot of ink.

Print heads can be replaced or repaired, depending on your machine, but if you are outside warranty this will cost, although if you save enough money using cheap compatibles this may not worry you.

Manufacturers cannot legally void warranty on a faulty printer that has used third party ink, but they can void it if they find that ink has damaged the machine.

The conclusion: the greater your ink use, the more benefit there is to choosing a high quality compatible ink. But pick a quality one, particularly for colour print work.

Divide the cartridge price by its print yield for a cost-per-print price. Compare results between cartridges and you can judge your savings on using a compatible. Over time you could save enough money to easily replace or repair your printer.

3. How concerned are you about your prints fading?

a. Not very

b. A lot

The hard truth about cheap compatible inks is that few have what is termed 'archival' quality - i.e., they fade. HP, Canon and the like have dedicated laboratories for testing ink recipes to maximise print quality. Their huge budgets allow stringent testing, and they need to: they have a brand name to live up to.

High quality compatible inks are available, but the cheapest 3rd part inks use low-grade ingredients and inferior production methods. And it shows in their life span. Independent tests show time and again that the cheapest compatible inks often last less than a year without fading.

Thankfully reliable compatible brands are available which last as much longer than their cheap competitors and in tests compare favourably with the OEM brands.

However, be aware that fading can be a result of using the wrong paper. For optimum results with any inks you need to use the best paper. But more than that, use the Right paper.

Instant Dry (porous) paper does not work well with the dye-based inks usually used in compatibles (for example Epson paper, designed to work with Epson's pigment-based inks).

Best results with compatible ink come with 'encapsulating' paper, made to work with dye-based inks, such as HP's and Canon's. Some inkjet papers claim to work with dye And pigmment, but check product reviews first.

Print life can be maximised and fading avoiding by storing prints away from humidity, air pollution and bright lights. Prints from dye-based inks are especially prone to ozone-erosion, and other air-based pollutants. These prints should be displayed behind glass to avoid fading.

The conclusion: OEM inks offer archive quality prints. Cheap compatibles fade but a good compatible can give you great results.

4. Are Green issues important to you?

a. No

b. Yes

Most compatibles use new casings that cannot be recycled. If your printer or its parts wear out sooner because you use cheap compatibles then OEM cartridges are clearly greener.

There are some good 'green' third party cartridges available which use recycled cases and come in environmentally-friendly packaging - shop around. Or you could refill your own cartridges with bottled ink.

Conclusion: genuine can be greenest, unless you find a reliable eco-friendly compatible.

5. How old is your machine?

a. A few years or more

b. New

If you're happy with an old machine you might bulk-buy cartridges. If you've found a great source of compatibles, fine; otherwise you're probably safer buying originals. OEM cartridges are more likely to be stable in storage, particularly pigment-based inks, which are less susceptible to drying out.

If you have an older machine which takes cartridges still used by newer models then your choice of compatibles will be broader. But keep an eye on the market when purchasing ink to avoid a nasty surprise if supplies dry up.

Newer printers often need 'chipped' cartridges. Manufacturers add chips to deter users from buying compatibles, and to control ink flow. The compatible cartridges use either their own chip or get you to reuse the chip from your original cartridge.

A big complaint about chipped OEM cartridges is that they waste ink. The chip says 'ink low', and the machine stops until you change cartridges. But tests show that as much as 30% of the ink is unused.

Good quality compatible cartridges now come prepared to bypass flawed 'low ink' messages, and come fully loaded with maximum ink quantities. An OEM ink cartridge often holds far less ink quantity than you'd assume from the cartridge size. Decent third party inks offer a lot more ink per cartridge.

The final conclusion: an ink seller with a high turnover is a better source than one where ink is stuck for months on the shelf, slowly deteriorating. Read the product reviews and experiment. Choose a compatible from a reputable supplier selling a named brand. A good compatible won't damage your machine. If your ink use is modest, original cartridges make good sense.

*trustedreviews.com - The Inkjet Investigation.