I second the Tri-Tronics. I have three at the present, two Upland Specials and a 100 LR and used to own a 70LR two dog model. I have had them for as long as 16 years and the only trouble I've had outside of routine maintainance was a poor seal that leaked water into the transmitter after it was dropped into the water. This was on my two dog model which I bought used and I believe the previous owner tried replacing the batteries himself. TT had a bad batch of batteries in the Upland Special when it first came out but they recalled mine, replaced the battery, and returned it in less than 10 days which I thought was exceptional. In my training club of nearly 100 members, TTs are by far in the majority, especially for the serious trainers and competitors. It seems those that get another brand eventually gravitate to a TT. The only knock I have against TT is they only support their product for 10 years or so. After that, they sell their parts and one has to get older units fixed by a third party. This was the case with my 70LR. I don't blame TT for this, there is only so long one can keeep parts before it starts to cost more than it's worth, but I have had good and fair experiences with them and wish to continue the relationship.