Update on how the HPI GT S tires, HPI firm foam, JConcepts Rulux 1/2 offset half ups combo went.
I have about 8-9 runs up on this combo so far and im pretty impressed. I've driven on various dirt surfaces, skate parks, skate bowls, grass. This was mostly bashing, some jumping and even some track racing(

). They have held up really well, lotsa grip, very little lateral tyre roll, enough cushioning for landing high jumps and cartwheels. Strapping tape is also holding up so far(probably because i only vented the wheels). Gluing is also still holding which i'm happy about as it was my first effort.
If a manufacturer starting making a 'medium' profile tyre to suit a 3.7 inch wheel that had built in belting and was a little lighter than the GT S i would love it