There is another option you may consider, but it is not the cheapest way to go. You can buy the Traxxas stub shafts, and remove the plastic couplers(Dremel), and the pin(punch or press). Then install the stub shaft and put a heavy duty coupler on the inside of the knuckle. Finally have RCAlloys make up a set of custom dogbones just for your setup($20 a piece). You can even specify the dimenssions you wish for length diameter, and pin size. I am working on this setup myself right now for one of my Maxx projects. The axles will be 8 to 10 mm in diameter for extra strength.
I cannot tell you what length to get, because I am also extending my arms by 12mm for extra stability and handling at high speeds, so my dogbones will be very long. I can pretty much assure you though that this setup will not break. If anything you may break the stub shafts under some real heavy duty bashing, but they run like ten bucks a set, for 4 of them at T/H.
You also have the option of purchasing RCM stub shaft adapters for mounting up 17mm hex adapters. These work perfectly when using Axial beadlock rims. There are always options to consider, but I always lean toward the heaviest option available to achieve what we call "BulletProof" builds. I hate having to stop playing due to periodic breakage, because of inferior material setup parts. SO there are some other options for you to think about in your quest. Good luck with that.
