I guess first I should give a bit of background.
My existing Hanna went into Calibration hell. I had to calibrate it, extensively, multiple times a day. Perhaps the tip was degraded, perhaps I was doing something wrong, either way, I was frustrated by the whole process. I saw .5 errors in the same sample taken 10 min apart. (whey and wine). I suspected the tip was the issue
So, when I saw the data sheet for the 110 model I like the part that said.
"Refillable pH electrode is easily serviced. Fresh reference
solution maintains high accuracy. Eliminates concern with
shelf life"It hit an understandable hotpoint with me.
I have no data on the lifespan of the solution. The datasheets indicate the following:
"The supplied container includes 15ml of filling solution. There is enough solution for 4 to 5
refills. Use only the supplied solution for refilling the electrode."So, when the meter says "renew" or "cal". I'm all over it.
But this is just my needs. You may not find that aspect particularly interesting. And truthfully speaking, there are other, probably better pH probes for cheesemaking.
For example, Hanna makes various dairy-related pH electrodes to be used with their meters
here. Some of the listed probes are specific to Cheese, some to milk, others cream/yogurt, and still others semi-solid milk products. These probes are are $100-$150 and are meant to be used in conjunction with a pH meter of some type. For me, those were too specialized and too expensive from a probe replacement perspective. I need to be able to use this pH meter for other than Cheese applications like wine.
So for me, the ex110 is a good quality (not great) utility-player pH meter/probe that satisfies my specific pH touchpoints and is versatile enough for other applications.
Anyway, sorry to ramble. Good luck with your decision.