Seeing as the front and rear suspension arms are the same ....
There should be no reason why, with some ingenuity, that the front C-Hub parts could not be installed on the rear, to allow toe tuning, and, with the right kind of bracket/mount to secure the required control rods, the tuning could/would function to allow toe change that changes with suspension compression ..... ( this would/could also apply to the 2wd Slash... )
I hope Traxxas starts sending sample Slashx4's to aftermarket vendors to allow them to get some jump start on creation of aftermarket goodies ......
I hope Traxxas starts getting accessories and replacement parts sent out as soon as the main kit starts shipping
I hope Traxxas takes some much greater initiative to offer additional aftermarket and tuning options, including tires, tire compounds, wheels, bodies, Lipo etc .....