I've tried most of the brands (Sport Dog, Dogtra, D.T. Systems) and the most reliable has been Tri-Tronics. They may be a little more expensive, but you get what you pay for. More than anything, the different levels of stimulation are a lot more consistent with the Tri-Tronics collars. When you tap them with a "low 1" setting you know that's all the stimulation they're getting. The other brands I've used were sporadic. You could set it on "1" and the dog would do a backflip because the settings were not consistent.
I will agree that Sport Dog collars have gotten better and have been able to get some nationally-known trainers to back them.
As far as only using them when training, my dogs don't hit the ground when hunting without an e collar on. I've had too many run-ins with snakes, hogs, bobcats, deer, vehicles, open oil-field pits, you name it to risk them not having "brakes and steering wheels".
