Get a OS .28 XZ. You will not be wrong. Are you sure you need top-end speed as much as on-road? You can torque/power to spin the big wheels on truggy and jumping. Torque is more important to provide acceleration for jumping.
http://www.rc-toro.com/product_info....c3928100e350a2
Also, get OS. Don't get SH, GO ..etc. OS lasts much longer, and more reliable.