Have had these now for about a month. Overall, I really like the product; however, I do have some suggestions for improvement (which is why I rated this four instead of five stars). First, provide a quick release collar. The belt-type collar is a pain in the neck (we did mark the collars to get a consistent fit), but it would be so much easier to have a quick release option that would ensure consistent fit and make on-off process that much quicker. Second, the fact that the light does not go green when the collar is fully charged is annoying. Yes, I can time it, but I would much prefer an indicator to let me know that they are fully charged. Third, it's not clear to me why they opted for a digital screen to show the setting rather than just have a wheel with numbers on it. I doubt that you need the precision indicated by the digital screen (e.g., is it REALLY necessary to know that you are at 35 rather than 31?). In addition, it's difficult to adjust this with one hand (unlike simpler designs) and the screen is hard to see in the sunlight. Lastly, an audio signal would be a really nice feature to add. It has the vibration and the "stimulation" features, but audio would be a value-add in my opinion. Construction quality is very good and the components seem to be very well made. I really like the dual collar controls with two different color buttons (rather than having to switch on the fly). I gave this four stars because I felt that the collar was made primarily to train hunting dogs, and I use it for different training purposes (some correction) and to provide cues (vibration) that facilitate commands. I'd love to see Dogtra come out with a model that I describe above.