re: Invisible(underground) dog fences-What features should I look for in a good one?

Sport Dog SDF 100

I purchased this about 3 years ago and installed it myself. Works great still. Within the first year, I believe lightning struck the loop in the yard. It was under waranty still and Sport Dog replaced it. I purchased a lighning protector for the second unit and drove a new grounding rod for it as well.

It took a full day for me to bury ~700 ft of wire. I used an walk-behind edger and went thru 2 or 3 blades.

My dog is really smart and very obedient, so training was pretty quick and she has never broken out. I followed the training suggested very closely and it worked.

Good luck