I was gifted the Milwaukee MW 102 pH/Temp Meter. It is a quality piece of equipment and I noticed that pFriem Brewing Co. in Hood River was using the same or a very similar model. Since I only use it about once / month I calibrate before each use.
I would suggest paying a little extra money to buy a decent meter that will allow you to replace the pH probe.
Just replaced mine after two years and 10 months (61 batches) typically used once or twice per batch. Cost about $35 for a new pH probe. Resolution 0.01 pH, accuracy (@25C) +/- 0.02 pH
If you are going to bother measuring pH, you might as well spend the money on a decent meter.
-Brewn'Z