They have both RTR and kit in stock. Mine is the kit one. The 1/8 kit is the smaller black box. The big colour box with a picture of the car is the RTR.
I think the major different is fuel cost. As 1/8 burn fuel faster than 1/10. Tires 1/8 last longer than 1/10. And the engine last longer than 1/10 too. But the main point. I personally think it is more fun than 1/10. I think that is the most important pt.
I think it is a little over 3000 for the rtr. With futaba servo, radio, .28 pull start engine, pipe, tires, painted body. And I think the parts are interchangable with the pro kit so you can upgrade later.