Im still running my old Mp 777 Sp2, the only issues that I have had with kyosho is the price of there parts. The kits are kinda a challenge to figure out the parts due to the diagrams but after you get it together it seems to be a prity solid buggie. I run a long technical track with alot of timming most of the time but every once in awhile I like an insanely fast track with some long jumps and crazy straight away's. I have found that there kits are easy to change the setup and the oils in the difs when needed.
Personaly I believe the only kit I would have chosen over the Kyosho is the Mugan's. I have seen some nasty wrecks and hard hits on the tracks. The only cars that I have seen drive away without something broken or motor mount slip has been the Mugan.

That is a very nice RTR but it does not come with a pro chasis and missing other pro parts which are vital in racing. Motor Mounts, steeing knuckles, Chassis Stiffeners and driveshafts are not quite what the pro kits are. All in all you are paying for this in a RTR: Motor say -$120.00
Electronics- $100.00 Tires say -$30.00 Roto starter-$35.00. (These being estimated only) So If you pay say $400.00 for your RTR about $285.00 of the price is Motor, Radio,Starter & Tires and $115.00 is what you are paying in the vehilce itself. A pro kit is going to cost you around $600.00 just for the Chassis alone due to the parts that the kit comes with. That is just my thought on the RTR vs Pro Kts not to mention the hedachs of servo failure and the roto starter nitemares everyone has with a RTR. Not bashing on your RTR by far it is a very nice Vehicle and it is alot of fun, they just do not hold up in racing.