Pro - inexpensive, easy to use, have not measured the max range between the units but definitely covers my small property!
Con - The probe lasted a little over a year with light use. A replacement cost $12 plus shipping
For a few more dollars, I bought a whole new set. This set does not synch as well as the other but once you get it, it stays!
Overall - I have enjoyed using it and the cost makes it worth a try.
We've found it very complicated to use. We use it when we make yogurt. The alarm works great when the temperature of the milk reaches 180°; it doesn't work at all when the temperature is taken down to 120°.