Well, I was a little sceptical at first but chose petTracer after our cat disappeared for 4 days but came back. He roams in the summer and we needed to keep tabs on him. After initial setup and learning how to use the system, we have been able to follow him carefully and worked out his main haunts. The only thing stopping me giving 5/5 is that the life is not as good as I thought on standard mode and the collar needs a charge every couple of days, which we do when he is resting so not a problem. He has slipped his collar twice as I did not want it too tight, and in the first case GPS was accurate enough to find the collar in a neighbours garden, and the second time we thought it was lost but the radio tracker worked a teta and we found it near some rubbish bins and out of GPS range - it really was easy to find and the LED light feature helped us this time. Experience is very good, support is excellent and well worth buying.