I got one of each color because we use them daily many times a day. All are working perfectly so far. I have put rechargeable batteries in for about 1.5 months and still haven't needed to charge them a second time. They have a switch on the side that turns them off so the battery doesn't drain unnecessarily and a magnet on the back if someone wants to put it on a metal surface. They are easy to use (a 5.5-year-old uses it by himself), with large numbers and the maximum measurement is 99' 59". I like that it also shows the seconds. It doesn't show the time, but the ones I had that did, the battery drained frequently and they broke quickly. So for me, VFM.