High Roller is awesome, IF you fix a few flaws with it first.
1- The driveshafts are rubbish, they bent under the strain of the stock motor, replace with C.V. driveshafts. Similarly, the little pins in the hex-drives are weak, put some stronger ones in, I just cut some HPI ones to fit.
2- The idler gear in the gearbox is surrounded by metal gears... but the idler gear itself is plastic. Whoever thought of that needs shot, it might as well be made of cheese. It WILL strip, and pretty quickly. The alluminium idler gear is essential.
3- I replaced the ESC with an Mtroniks one. There's nothing wrong with the stock ESC, only it doesn't allow you to go straight from reverse to forward, preventing wheelies. And what's the point of a monster truck that doesn't wheelie??
4- The standard radio equipment is, frankly, crap. No range and prone to cutting-out and interference. Swap right away.
It may sound rubbish from what I've said, but trust me. It takes one hell of a beating, it's ground clearance is amazing, it looks great, it can go anywhere and it's really well geared and quick as standard. I do recommend it.
Infact, only last night I was out with a few friends charging our R/C trucks and buggys around a farm. There was a massive pile of gravel, the High Roller caught about 8 feet of air over it, time and again. No problems whatsoever!