A few caveats. Make sure you find one that has probes that are enclosed. The one I use has a suction cup on both sensors (fridge and freezer) as well, so you can stick it to the wall of the compartment and out of the way. I prefer the wired ones, even though they have to go between the door and the seal. No extra batteries to replace in the sensors and if you route them correctly, you'll never notice the wiring. Most of the remote thermometers allow you to set a temperature alarm. that means if the temps get too high it will let you know. How's that for some additional peace of mind?
some basic maintenance on your fridge before departing on your first trip. It's easy and will confirm your refrigerator/freezer is working at it's most efficient. If you are going to be in areas where high temperatures are the norm, you may wish to install a supplemental exhaust fan for your refrigerator. I've been using the digital thermometer for a while now and it works great. Make me less prone to food spoilage anxiety! As an added bonus, my drinks are just like I want them Cold and delicious.
Be Seeing You...Down The Road,
Rich "The Wanderman"