Pretty tuff to beat the Dogtra remote release electronics..very long lasting batter life between charges. (3-4 weeks with normal usage) It can operate as many as (6) receivers, that can be added as needed. (by the factory) The RRD has a realistic duck call sound (not the electronic beep like TT) It also has an optional external speaker which increases sound volume thus carrying better at a distance.
If a more realistic duck sound is what you need then the dogtra is better. For my normal training, a Tri Tronics is better as several of my training partners have them. We can program all the receivers out in the field to work on one transmitter. The one partner I have with Dogtra we can't and have to use his transmitter. He also had to send the whole kit and kaboodle to the factory when he bought another Gunners Up. I've bought extra receivers off of ebay and they program into a TT transmitter with a couple of button pushes.
Another thing we often do is set up two launchers at the same station. We use a homemade extension wire to attach one receiver to both launchers. Saves carrying out another receiver. Can't do that with the Dogtra.