Fi Series 3 vs Halo 3 Dog Collar - Which is Better for Your Dog? 

I do not recommend the Halo company - they refused to credit a purchase I sent back unopened. I purchased two of these Collars and first tested it on my one dog it was so unreliable I decided to send the unopened one back.

Fi is lousy and customer service is terrible

I live in the city, so my dog is rarely not by my side and if she is she's a room or two away sleeping. Fi Series 3 fits my needs because of that, if I were in an open space environment I'd want something with faster updates and more accurate tracking. Generally takes about 2 - 3 minutes from when we've actually left the house to notify me that she's not in her safe zone. Mostly just use it to track her activity at this point, but if she ever did get lost - since I'm in the city - that 2 - 3 minute window isn't too awful for finding her. It has some other small things like mentioning that you've visited a dog park, and being able to alert all other Fi users in the area that your dog is on the loose, but overall as I said it's most useful as a way to track her activity and maybe get ahead of anything wrong with her health based on trends. It's accurate in the routes we take when I walk her, but doesn't show any of it until after the fact. Can't speak to their customer service, haven't had a need. Their help bot on the website is pretty terrible, though.