Works great. Walked thru with our German shorthair pointer one time and he had it down pretty good. He was around 6 months when we got it. No problems with it yet. We got a second transmitter to expand the barrier.
I have a 45 # Goldendoodle that is almost 9 yrs old. She was 6 months old when I purchased this wireless fence. She adapted within 2 days; it was set on 2 and she has never crossed the boundaries. She has never gone beyond the beeps.
We have a 2 year old friendly lab who loves to walk in the road and go visit neighbors. This wireless fence has been a great solution and has kept her safe as well as save our sanity. She has plenty of room to roam in our yard but we no longer worry about her going in the street or running up to neighbors out walking. Took 2 days to train and has worked perfectly every day since. We also travel frequently and can take the system with us and keep her contained in other yards or at a beach house, etc. All you need is a single electric outlet.
We have the collar batteries auto-delivered every other month, as the one on the collar seems to last a little over 75 days.