I will add my two cents. Beau had problems with the ears, and maybe because I was using my own meter, and it required TOO much blood. I switched to the ReliOn micro, but my advice is to find a meter that requires the smallest amount of blood possible. This Relion only needed a tiny bit, so small you could barely see it.
Also, I found myself not wanting to prick and hurt him, and ONE TIME, I tried his little paw and it worked for me on the first try. Unfortunately, he got very ill from so many other things, and he got his wings yesterday, but had he lived, I would have tried the paw.
I firmly believe though, that they need testing before insulin. I had techs coming here twice a day to test him. If they could not come to me, I went to the Vet. I'm diabetic also, and in these last few days tryign to save my beloved kitty, my sugars have dropped from 450 or so (very bad diabetic here) to in the 100s. Not sure it was stress; forgetting to eat; what. Not an expert, but I would guess the same can happen in our fur babies. We don't really know what's going on inside, and to guess and dose and then find out their sugars were already low is not good. BTW, Beau had sugars close to 500 when we discovered it. His last few testings were around 130 or so. Not sure whether it was what he was/wasn't eating of all the other things, but just please test.