"Tollers like to do things their own way and can be a handful, usually a lot more so than labs."

That made me laugh. I understand about hard to train dogs. I use to run Chessies. Would never have thought about a electric collar unless you could have found a 220 volt version, 440 volt better yet. Well to be honest, e-colars had not been invented until the last Chessie I had. Chesapeakes train themselves as much as anything. Had one who use to bite your boots if you missed more than one bird. Brute was so tough he would bust or even bite ice to get to birds. You could not wear him out. The harder he worked the happier he was. I miss that old dog.

I am most interested in a vibration stimulus with GPS location. Most of the shock training I have seen is so poorly done, I vote for the trainer to wear the collar. Just like yelling is not a training technique, I do not think lighting a dog up as one. I want attention, not instant compliance. Give the dog time to figure out what I need by giving her a bit of extra reminder. After all, it is my job to teach her what I expect and to put her in the best position to achieve it.