It has probally been worked out now, but at one point someone was having trouble with dogtra remotes on a max. The sound of the max damaged the remote. That is something I would ask about if I had dogtra remotes before buying from etch mark.
I have two 4 shooter thunderbirds with tri-tronic releases. I like mine so far but haven't gotten into using them very much. The second one I bought had some refinements over the first, and they probally worked out the original problems. Inherently, it is probally a more fragile device than a bumper boy but you just have to realize that. The bumpers are a little different, but the bumpers on a bumper boy aren't exactly ordinary either.
My experience with bumper boys is limited because I don't own one, but I can see why they are better in a lot of respects. I still like the thunderbirds though. Dogs really like them too. That shotgun sound and that bumper wobbling through the air at a hundred miles an hour gets them excited. To me it is fun gizmo that you would put on the carpet of your truck's interior instead the rubber mat of the bed when riding down the highway. I'm probally underestimating their durability but don't want to take any chances.