UPDATE June 10, 2015: This is still running along like a champ. It keeps on telling me how truly warm our bedroom is, even with the A/C running! (Right now, it is 82 degrees at 2 in the morning, with the A/C, a ceiling fan and a box fan running. Eww!) In fact, after a few days of looking at the really high humidity in here as well (the roof of the little house turns black when it gets higher than it should be), I am back on Amazon, shopping for a dehumidifier. (We rent, so we cannot just get a new A/C unit etc.) By the way, we have not had to change the battery since we bought in three years ago, so it doesn't suck through the batterie either. Great little unit! ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ I have to say that I really wanted the blue one, but the tightwad part of me said to save a few bucks and get the black one, in case it doesn't really work. There are a lot of mixed reviews on this item, so I wasn't sure what to expect. I wish I had had it during our recent extreme heat wave (over 100 for two weeks in a row, with killer heat indexes).Of course, it might have been even more depressing to see what the inside temperatures REALLY were like! We have a temperature gun that has the point-n-shoot laser that gives instant feedback on the temp of any given surface. It works great, but it's my husband's maintenance toy, and I couldn't keep it all the time. So, I looked for my own toy. This one certainly fills the bill. I kept his gun up here for about a week to double check the temps on what it said vs what the monitor said. It was very accurate. Now, I didn't have a way to measure the humidity with his temp gun, but I can tell that by how swollen my ankles are! ; ) So far, it works like a champ. If I was to change anything at all, it would be to have some sort of hole to thread something through to hang it up. Right now, I don't want the magnet around my computer equipment, so have to watch where I put it. I have nothing metallic to attach it to, so it is sitting up on my desk, away from my CPU. The display is large and easy to read. It started working immediately upon putting in the batteries. (It takes only one (1) alkaline AA battery. Of course, no clue how long it will last yet, but only one is great!) Bottom line: I'm glad that I got it. I like to know the basic temp/humidity level in the bedroom where I have it. Our older-than-dirt apartment has almost no insulation, so whatever it is outside, we are usually just a little bit cooler inside, thanks to a black roof and brick sides that retain the sun's heat. Great job, Acu-Rite - it works like a champ! UPDATE 07-23-12: I do have one bone to pick over this item. Having used it a little longer now, I now see that the highs/lows to the right of the temperature or humidity level are only for the LAST 24 HOURS!! Instead of showing the highest temp in the room or lowest, it is only the high/low for a one-day period! That kind of stinks. I realized what it was doing when we hit a high of 92 in the bedroom (with the A/C running, ceiling fan and box fan - I hate this heat wave!), and that temp disappeared when it cooled off over the weekend a little bit (to a temp of "only" 81). Now both the high and low are 81. That part isn't pleasant, but I wanted to mention it, in case anyone was trying to track how hot/cold it gets in a particular area. You'll only see a max of 24-hrs of info, and your old data will disappear. You'll have to track temp changes manually. The temps do seem accurate, but the lack of actual high/low storage is a bit disappointing.