“Is an invisible fence good for my dog?”
In a word, no.
Here are four reasons I don’t recommend invisible fences:
They don’t keep the bad stuff out. A physical fence is a major obstacle to other dogs and predators getting into your yard and harming your dog. An invisible fence offers no protection.
They aren’t guaranteed to keep your dog inside. Some dogs are willing to take the hit to exit the yard if what they want on the other side is attractive enough. Obviously, dogs can escape physical fences too, but it takes more effort than crossing an invisible line.
They may keep your dog outside. Once he’s escaped, your dog can’t get back inside without another hit and it’s usually not worth it.
They create negative associations. Your dog sees a person or dog outside his yard and eagerly runs up to the boundary to greet them. Then he gets shocked. This can cause him to dislike people or dogs because they predict discomfort.
“But my dog isn’t getting shocked anymore. He listens to the warning tone and stays inside.”
This is still a problem for me because the tone is basically a threat: ‘back off or you’re going to get shocked.’
The dog is changing his behavior to avoid something unpleasant (versus changing his behavior to acquire something pleasant).
Philosophically, I choose not to use avoidance-based methods or tools for training or living.
“But we do have a physical fence and my dog keeps escaping. I’m worried he’ll get hurt if I don’t add an invisible fence.”
If he’s going over, try coyote rollers.
If he’s going under, try L-footer style fencing.
Regardless of how he’s getting out, I’d also look at why the dog is outside alone AND I’d look at increasing enrichment and possibly appropriate physical activity so he has fewer opportunities and reasons to escape.