My up close experience with a Bikes Direct bike was Windsor carbon fiber road bike (with "Ultegra" build) we got for my wife. It was pretty decent for the price, but some less obvious corners are cut. The QRs were really crappy. The seatpost was heavy and low end. The tires were wire beaded.
The one big thing that stuck out were the wheels. Essentially no-name hubs, straight guage spokes, and entry-level rims. tI had to re-adjust the hub bearings because they were way too tight.
Overall, I think it was still good for the price, but the take away here is don't be duped into thinking these are some crazy good deals just becuase something has a few upscale components highlighted.
Other than needing to adjust the hubs, the assembly was nothing unexpected. I needed to adjust the brakes and shifters, but I was expecting that.
From my experience with this bike as well as two mountain bikes that friends bought (one HT, one FS), it seems to me that the wheels are where they cut a lot of the cost.
You need to be careful lwhen you look at their comparisons to "similar" bikes from big companies. In many instances they will gloss over some important things, such as they might say that both come with a Fox Fork, but they are not the same model.