i bought a Motobecane LeChampion SL Ti road bike from BD.com back in may. i've been using it pretty much everyday since then as my fair weather commuter. i've got over 1,500 miles on it now and it's been an absolutely perfect bike right of the box. what's most ridiculously shocking to me is that i haven't even needed to make a single derailleur adjustment in those 1,500+ miles. i've never owned an ultegra drive-train before, so maybe that's it, but i've never heard of a derailleur bike not needing some amount of adjustment after it's been ridden a while and the cables have stretched out. weird.
the biggest pitfall i can see with going the BD.com route is sizing. fortunately for me, i have an uncle who is in a riding club, and i went out with them one day and rode all of their bikes and took careful measurements and notes and then compared those with the geometry charts on the BD.com website for the bike i wanted, and sure enough, the dimensions on the 53cm version of the Ti LeChampion were just right for me. and after 3 months of riding the bike, i can confirm that the sizing worked out perfectly for me, but not everyone is so lucky.
overall, i'm completely and totally pleased with my BD.com purchase. i now have a full ultegra titanium rocket commuter that only set me back 2,000 bones. how freaking cool is that?
my uncle (the same one in the riding club) has also purchased several bikes through BD.com for his wife and children and has been very satisfied with the results as well. he was in fact the one who turned me on to BD.com in the first place. i in turn also tuned my other cousin into BD.com and she purchased a bike through them last month and has been very satisfied thus far. so no BD.com horror stories from where i'm at.
i love my BD.com bike:

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