I don't recomend the 727 until they straighten out the trim issue. It makes hand flying the plane on departures and approaches a hopeless case of flighting the airplane.

If you do buy it you can build real world routes as follows. Go to flightaware.com / pilot resources / flight route analyzer. This site will give you recently used real world routing between two points.

Buy the program FSBuild and plug in the route from flightaware.com. FSBuld will build the flightplan and plug it into FSX for you. Open the FSX flight planner and load the flightplan.

FMC's use airways and VOR's as well.