If Pacers is putting on the race, you really kinda can't go wrong. They have excellent organization, well stocked aid stations, and generally speaking decent to scenic courses. The GW Parkway Classic is one of those races that you can't run in DC without seeing 5 other runners wearing the shirt, and that ought to tell you something about the popularity of this one. The course is all rolling hills from Washington's estate in Mt. Vernon, running along the Potomac river and finishing in scenic, Old Town Alexandria. I would hands down run this over the Cherry Blossom 10 miler given the choice, and I wouldn't regret the decision in the least.