This is your typical checkpoint sprint race where you have to use the provided vehicle to reach the goal within the time limit by passing through the checkpoints at fixed locations along the track. You don't have to strictly follow the roads or tracks; as long as you pass through the checkpoints, you can use shortcuts. In fact, it is also encouraged.
For this challenge, you can use any vehicle of the same type as long as you unlocked them. If you're having problems getting the best time with the default vehicle, you can always try the challenge again with a different vehicle.
Unlock by: Vico Tructa
The starting part of this challenge is a short off-road part, followed by a long highway path which leads to a base with tight turns. Near the end of the course, you’ll have to make a long, daredevil jump so make sure to pick up speed and use your nitrous to get a good jump. Control your landing and it’s pretty much a straight stretch from there to the last checkpoint.
Unlock by: Reaching the province after completing “Connect the Dots” story mission.
The off road track is fairly manageable with small ramps and surprise checkpoint placements. The default vehicle seems to be a good choice for this challenge because of its speed and maneuverability.