Start beyond Callander Howard. Go well beyond Inverness, and see hundreds of miles of empty roads. Watch on You Tube when Harry's Garage went up last March in his Fezza. He gets it. Watch Highland Cops on i Player. OK they get some horrendous accidents occasionally, but the roads are empty apart from peak season. Keep away June-August. It's hard to get there, even from Yorkshire, and hard to get to, means quiet.
The SouthWest is now too easy to get to so is congested. When we go, we travel early hours both ways to miss the traffic, and don't drive around when we get there.