I have been a part of 5 different Bikes Direct purchases as the buyer or the person doing the initial assembly. I have never had a bad experience, even with some of their lower end bikes. My primary ride right now is a Motobecane Le Champion. I love it. Someone suggested earlier that you search the forum for threads on BD bikes and you will get lots of opinions. Opinions don't really count. Experiences do. Overwhelmingly people have positive experiences. You have to know how to adjust brakes and derailleurs or be willing to have a shop do it.
I have also ordered Nashbar bikes. Once or twice a week they offer a 20-30% off coupon. That makes some of their bikes a better bargain than BD.