We just think that a leash or having us yell "Heel" every few feet is less fun for and less fun for him (we think) so we were wondering if there is something like an invisible fence device that can give him the freedom to run off 20ft or so but remind him to stay relatively close if he strays/lags too far.
Ah yes, fun for the dog. It is important, isn't it. Crucial really.
If you're concerned about FUN -- and you probably should be -- well then, DON'T shock the dog. Find another way that's in keeping with the fun aspect, and doesn't punish your dog for simply being a dog.. I mean, obviously, getting zapped in the midst of a nature walk just ain't a dog's idea of a good time. I'm sure.
In other words, positive reinforcement training of 1) an acceptable "zone" and also 2) recall under high distraction.
There you go. Fun.