This is my second Dogtra IQ Mini. I love it. I do not have a fence but I can still let my dog out and not worry about him wondering off. I use the vibration mode the majority of the time. The shock mode is for emergency use. I let my pup out one morning and did not notice the deer in my yard since it was dark out. He went to chase them and I got him to stop with one tap on the shock setting. Before using you need to turn all the way down and test on yourself turning it up very gradually until u can just start to feel it. That is the setting you should then use. I recommend this color to everyone when they ask about it.I use this for my Shizpoo. She’s a barker. I only use the vibration. But sometimes I’m afraid I’ll accidentally hit the zap button.The additional collar is charged but doesn't sync with the transmitter, rendering it useless and a waste of money. ?I am a professional dog trainer. I use e-collars daily with my dogs and client dogs.While I want to love the Mini IQ for its design and ease of use, there are some issues with that make it impractical as an effective dog training tool.Reception - The reception between collor and remote is very poor compared to others on the market. I have found that even the slightest obstruction like a hand in front of the remote, from inside/outside a car, even just across the room can cause reception to fail. I sent in my particular collar/remote to Dogtra. They analyzed it and said that there as nothing wrong with it.The Dial - There is no way to lock the intensity dial on this unit. That means while the collar is hanging around your neck you can inadvertently turn it up to 100, or down to 0. Then when you need to use it on a moments notice you end up giving the dog a much stronger correction than needed. Or no correction at all.Battery Life - After 6 months of use I have found that the battery life is limited to about 1 day, depending on how much you use it of course. Comparatively, I have found that the Micro Educator battery life can go for at least 2 days.Customer Service - Last note I will add is that during the process of getting my collar looked at by Dogtra, some people on the customer service team were nice and helpful, others were not. I had to follow up multiple times about my collar. They didn't seemed to pleased or apologetic about helping me figure out one of their products that is less than effective in its current state.Overall, I would not recommend this product to my clients or other dog owners currently. Right now I am having my clients using Micro Educator. I hope to someday believe in Dogtra again.I did a lot of research before purchasing this, and I am happy that I did. This works great and is very easy to use. I have always been a little hesitant to use this sort of product, but the key is really as easy as reading and following the instructions. If you don't, and you get a bad result...then it really is your fault.Just always use the lowest setting possible to get your dogs attention, and then train from there. These are training collars, and you still need to do the actual training. Also, take the collar off of your dog when not in use and/or at night time. Don't always leave it on.Anyway, it works great and I would recommend it to any responsible pet owner who will take the time to learn how to properly use this trainer.I just received the IQ MINI. I have always had two other brand manufacturer electronic collars (5 units in total) so I have had many units. I am very disappointed in the “rheostat dial”.......the dial does not have a locking or click in place mechanism to prevent the dial from inadvertently moving to a number much higher (or lower) than the intended static level...it would be easy to be holding the transmitter thinking the correction would be at 20 as set, but it moved 40 or 60. The correction should be swift with a push of the correction button, but now I have to look prior to each press of the correction button to make sure it has not moved....The reason I bought this collar was the size (my dog is 12 pounds) and I’m stuck in Boston during the Corona Virus and my other collar/s are in Florida....In my opinion this is a design error......Because of this I would not buy. The receiver size is great and smaller than my other collars.I would give this a 3 star as it doesn't work well with long or thick coats dogs. After calling the company to see if there is anything we can do they politely mentioned I should've purchased the IQ Plus or another model with a different contact point. Customer service was great but would be nice to know in the product description that this is best for short hair dogs.After cutting my dogs bold in a spot he only feels it once it's up to about 40 and at that it's more of a tickle. I'm not comfortable using the product for basic training at 40 as some corrections may be stronger than others depending on how much fur gets between the contact point.I was happy to find units for my small (less than 15 lbs) dogs. The pager functions works well. Fortunately, that's what I use most often. Unfortunately, if I need to use the "shock" feature, I have to set the dial to at least 40 before anything happens. That is WAY too high for small dogs. I've tried it on myself and find that 40 is painful. Use with caution.