I was very happy to see an ecollar for 2 dogs, 1 remote at a very affordable price. This collar (along with training) has given me the ability to have both my dogs off lease and to correct their bad behavior successfully. I am not a fan on the shock mode (its on the lowest and never use it but I guess it's a good caution), the beep and vibrate mode do the job!
6 Months into the use, 1 of the collars stopped working. I emailed Pet spy and they were SO QUICK to respond and send out a replacement.
I have recommended this product to so many other dog owners!

These work very well. We have two German Shepard puppies. The transmitter (the walkie talkie looking thing) feels very cheep and light weight, but has held up well. The collars are holding up, but as the two dogs chew on each other, the receivers and collars are showing some wear (teeth marks, cuts, dents, etc.). The receivers feel solid and well made, but some of the buttons don't work well now due to some high bite pressure.In general the dogs learned to pay attention to the buzz. I don't ever use the shock button on them, but it's nice to have. I do wish that the transmitter was a bit easier to use (for switching back and forth between dogs).The controls are simple and straight forward,
These are a good product and I may buy another set once the furry children grow out of the chewing stage.

Training collar works well. I only use one collar, but the controller does work for both. It says you can use these for smaller dogs but since the larger dog responded immediately to the lowest setting, I feel that it may be too much for a smaller 15lb pup, so I still run around with two controllers in my pocket. Our larger 50lb dog responds very well to the tone and vibration features, so I would only use the shock as a last resort in an emergency situation. Seem to be fairly well made and so far keeps charged for several days. Not as substantial as the one we have for going out hunting, but good for everyday use as needed around home.

Ok was excited to get these collars as I was having a run-a-way problem. The instructions were not very clear and I had a little trouble getting the crazy things working- and the buttons are working better the more they are used. According to the instruction- only one dog should be "trained" at a time ( which does make a lot of sense), but my problem was that the dogs only run off when they are in pairs! Other wise my 7 year old and 3 year old dogs came when called etc., but living on a small ranch the dogs would go a pretty good distance, actually stop and turn to look back a me when called, then run into the woods for 3 to 5 hours! After a week I am happy to report I am starting to have some success at both getting the dogs to stop and having them come back after they have made the break to the woods (can't monitor them constantly, so they still seek off). I have even gotten them back from a rabbit chase. The older dog has only responded to a good level shock (4 bars) after ignoring tone and vibrate. The thing is that I have only had to use it a few times. I also discovered that the collars need to be fairly snug to work properly and I check their necks every day for "burns" or irritations as the dogs have short coats. Water-poof part seems good as the younger dog finds water to get in every day!

All in all I've been quite satisfied with these unites over the last several weeks. At this point I've had about half a dozen different models over the last 2-3 years ranging from Dog Widgets, iPets, Cujo Control, and Aetertek and so far this one has been about the best. The unit has a lot of a good features, solid range of vibrate and shock levels (don't even need more than 4-5 out of 8 for my 120+ lb stubborn pyr), and a reasonably good layout for the controls. Can switch between collar one, collar two, and both collars simultaneously (would be nice if there were separate controls like on some Aetertek and the DogWidgets, but still). It covers a good distance (provided you have that set correctly, otherwise it may fall short), the vibrating mechanism doesn't get stuck when using it (I had continual problems with that on both iPets and Aetertek), the beep is reasonably loud and annoying (my hound hates it and responds to that best of all), and they are very quick to charge (less than 30 minutes) with the units lasting throughout the day (almost two days before they did finally go empty). I've only had to resynchronize the collars once and I believe that had to do more with the fact that I had allowed them to completely run dead on the battery the one time.

Probably my biggest gripe with these units are the auto-sleep functions on the collars since the gyro sensors in them are extremely insensitive, so when the collar goes to sleep I often times will actually have to take the collar off and shake the snot out of it for 3-6 seconds to wake it back up. I expect this is probably the source of a lot of peoples frustration where they had seemingly defective units. Sometimes it isn't as bad and a few good finger flicks will wake it back up, but usually it takes a fairly vigorous shake for several seconds, so for me I just have to make a point of checking them each and every time before taking out both my dogs since even at a full run it may not be enough to wake the collar back up prior. That being said these are still the best training collars that I have used to date.