I have a Tri-tronics and I love it. Before I got this one I had a two dog from DT Systems. It was ok, but sometimes I had trouble getting it to work. The tri-tronics works great. It has a mile range and you can get them with up to two mile range. I don't know if it will reach a whole mile or not, but I know it will reach a long way. My dogs have never gotten out of range. I have a three dog classic 70. I recommend getting a three dog because if you have this many dogs you will want them. I started out with a one dog, then bought a two dog, them had them made into a three dog. If I would have known what I was going to do I could have just bought a three dog and saved about a hundred dollars. I don't know anything about dogtra, but I highly recommend Tri-tronics. Once you get it you will realize it was worth every dime you spent on it.