I have used the Sportdog brand for my first lab and used it hard – many upland and waterfowl hunting trips plus training for hunt tests. Being one of the smaller and lighter collars on the market was a factor for me as I was running my dog in SD pheasant hunting where the dog can run up to 30 miles in a day (3X my 10 mile pedometer indication). So keeping a light collar on her I feel helps her out o long hunts. The collar is good and never had any issues with it, but after three years of hard use, it finally quit working as the shock/nick button would not work and the collar stopped working. To fix these collars and the cost, it is better to buy a new one.
Now that I have two pointing labs, I have purchased the Dogtra 2500T&B system and absolutely love it. With Sportdog, I had to purchase an additional pointing attachment which increased the weight. With Dogtra, it comes built in, has more settings and more control and have not had any issues with it in nearly three years. A bit more expensive, but, now that I have thoroughly tried both products in harsh conditions for quite some time, my personal preference is Dogrta.