It is electric, with a full mechanical brake set-up from the nitro kit.
A little more flexible than motor brakes, affords you adjustable front/rear bias etc. I've set the controller to full race mode, no reverse, motor brakes disabled. Mixed the throttle into the radio's auxilliary channel and it actuates the brake servo. I managed to get it set up nicely and works very well.
Also, there's the Tekno Traktiondrive system fitted which is basically a nitro clutch, smooths the delivery a little more. Not sure it's essential.
That motor is actually Truggy specific, it's the larger can Tekin and rated for 6s LiPo (my main reason for using it). Gearing depends on where/when etc. With a 6s pack it's pretty quick. It can handle being geared up quite a chunk, ESC's very decent and the motor obviously likes sucking up power as it's a low kv rating.
I built everything with racing in mind (well, sort of), thought I'd give all the gizmos a try.