It's definitely a 5 hour drive from Manchester Airport to Edinburgh, including a decent stop. One key question is which golf courses you want to hit, and how long a tour you're planning. If you're blasting up to the St Andrews area, then it's long drive; if you're heading to the Borders or the Ayrshire coast, and then moving on, the drive is shorter, and a plane from Manchester to "anywhere in Scotland" won't help you that much. If more than one person drives, you can do it by car easily enough (with as stop and a driver swapover); the route is easy, it's more the distance and the timing (just after a night flight) which are the problems...