You guys have summed it up very well.
Its a great car, and there's a lot of support for it - i.e. email anyone in the team and we'll be willing to help, and probably give you more help than you bargained for... thats because we're all enthusiastic for the product, it really is superb.
Russ is slightly wrong with the ratio though, its the other end of the scale
. With stock drive train it is 1.75:1 which means it needs a really big spur to slow it all down (I am using 110 tooth). Which means when the motor is spinning like the clappers, everything between the pinion and diffs (not including the diffs) turns 1.75 times to turn the wheels once. This means all the bearings, belts, pulleys are capable of such revs, and the car accelerates smoothly.
I run a XX4 layshaft gear on my X-5, and this lowers the ratio further to 1.66:1. I think this is the best gear for the car, along with the DDP diff gears.
Compare this to an Academy which I have experience of too, this has 2.75:1 internal ratio, so the whole drive train from the pinion to the diffs turn 2.75 times to turn the wheels once, and I found this to shake the car apart (literally), and it fried any motor I put in hotter than a 12x1.
When I ran brushed, I could happily run an 8x1 (Reedy Ti - still got it) in the X-5 and it'd still come off cool enough to touch, cooler than my 2wd with a 10turn in.