I have been using meters bought on eBay since April 2009. Back then, I had a doctor friend order some test strips from a medical supplier, and it saved me a LOT of money for the strips.
Perhaps I was smart to get a ProTime meter, rather than a CoaguChek, because the ProTime runs two or four quality tests each time a test is run. Sure, it takes a bit more blood, and the strips require refrigeration, but I think you can be more confident about the results than with the other meters that require occasional quality control tests. Also, because all the blood is held inside the strip, there's no cleaning under the lid that other meters require.
I don't work for or consult with any meter manufacturer or distributor, and these are only my opinions, but I've been happy with my ProTime. (When I wasn't quite sure of the 'new' machine, I ran a test on my non-anticoagulated wife and got a .9 -- close enough to normal to be pretty confident. I had an unplanned confirmation of accuracy in December, when I had a concussion, and a hospital lab got an INR of 2.92 on its test...I tested my blood the day before - 2.9).
I have noticed the prices drop considerably for all the earlier generation meters. What the sellers don't want you to know is this -- these meters were new, used in hospitals, stored on shelves as backup machines in government hospitals, etc., etc., and were treated as 'capital' equipment. This means that, each year they had the machines, they wrote off a portion of their cost. After the meters were written down to zero - fully depreciated - it was time to dispose of them. Many meters wound up being liquidated or sold at auction, and now these 'cheap' meters - that were, in many cases the accurate workhorses at health care facilities are becoming available, often for very low money.
The meter manufacturers are careful NOT to release meters that are inaccurate or don't pass internal testing. The meter manufacturers' risks are too high to release defective meters - and probably either destroy or repair any meters that it finds, internally, to have problems. It's mostly THESE meters - perhaps a few years later - that are being sold on eBay, from what some vendors have told me.
I recently bought a CoaguChek S, brand new in the box, for a ridiculously low price I won't even mention. These were apparently sold off because they were part of a kit - Meter plus Strips, and the strips expired. The meter was still new, perfectly good, but unsellable as part of a kit because of the expired strips. Apparently, the company that built the 'kit' wasn't able to sell just the meters by themselves, so they had to dispose of the meters - very inexpensively.
Eventually, I'll probably do a QC test on this meter - but, for now, I'll probably test some non-anticoagulated friends and see how close they get to a 1.0. I'll also be simultaneously test with the CoaguChek S and the ProTime and compare the results.
I upgraded to a ProTime 3, apparently bought from a health care facility that was clearing out old meters (or something), for a very low price. I really like this meter.
I've seen ProTime meters on eBay, often for $50 or less -- and this, I think, is directly related to the sell off of fully depreciated (financially) units that were perfectly useful but were sold off because they had no depreciated value.
A few weeks ago, I got a ProTime meter that appears to have only run 6 tests - the last one in 2004. (The ProTime Meter shows the last 30 tests - storing them in Flash Memory - and this meter ONLY had six results overall. It was as new a meter as can be imagined. I'll run a test with this one, comparing it to my CoaguChek S and my ProTime 3 to confirm its usability). I bought this meter for $1 plus $5 for shipping - and it included the power supply, videotape instructions and a manual. It cost this seller more to ship it than I paid for the meter.
Some sellers will let you make an offer - so even the listed price may be flexible.
So -- long story short - I personally wouldn't, and haven't, been too concerned about buying a meter on eBay. With perhaps a few exceptions, these meters were reliable, valuable tools in medical practices in the past - and still should be. Ross loves his seven year old meter - these old meters on eBay are probably equally worthy of amorous feelings. Because of the QC performed with each test, I'd probably be more comfortable with a ProTime than with a CoaguChek or CoaguChek S unless the meter does concurrent quality control (which I think InRatio also does). I'd be a bit more concerned about buying ProTime strips on eBay because they don't survive long without refrigeration and it's hard to be sure how well they've been treated while waiting to be sold.
Of course, don't assume that I'm TELLING you what to do. I can't and I won't. Whether to pay $80 for a meter on eBay or $800 for one from a medical distributor is entirely up to you. If you think the $80 meter is a risky buy, don't buy it. If you DO buy a meter on eBay, it makes sense to compare the results of tests made on that meter to those of another meter with known accuracy or with lab results. (An easy test, too, would be on a person not taking anticoagulants -- though this may not be the best way to verify a meter's accuracy, if the results are far from 1.0, I'd be concerned about the meter) Be aware that some meters (the CoaguChek S and XS, for example), have been shown, when compared to lab tests (results are in the Professional area of the Roche CoaguChek site) to often report higher INRs a bit higher than lab tests show. Comparing a CoaguChek S results with a ProTime, for example, may show a higher difference with an actual INR of 3.8 than it would an actual INR of 2.5.
What may be most important is consistency -- if your meter regularly shows a 3.8, when a lab may show a 3.5, knowing this may allay concerns about a high INR being not quite so high. If your meter suddenly shows a 7.0, or a 1.2 - then it's a clear indication that YOU may have a problem and need to seek medical care and/or adjust your dose.