Have a Langster, but looking at the frame specs, they seem similar and I would go w/ the langster just for the fact that it has dropout protectors. If you are running a nut, aluminum dropouts will get eaten up quickly.

Both have integrated headsets, are butted aluminum, have shaped oversized downtube, so I would not see much of a difference in feel. Langsters have the same geometry as an Allez, so if you like how that bike rides....

I am not sure of your priorities, but if weight is a concern, I would steer away from pakes as others have mentioned. Those are tanks. If you feel the bare langster frame and compare it to all but the nicest steel tubed frames, the Langster or Bowery will be lighter by an easy pound.