Fine little device
I coordinate a statewide group of volunteer lake water quality monitors. Many of our volunteers use these to track the depth and timing of lake stratification (or where and when the thermocline develops). They are easy to use and accurate enough for our purposes when compared to a YSI EXO3 (a fancy and expensive science doodad). I only wish the battery life were longer so we didn't have to replace the entire unit every 5 years, and would love if it could record in half-meter increments.