Kyle provides a great service for those considering law school, but he does have some gorked numbers from time to time. I can close your gap a bit (see from individual school report links below), but your main point is that yes, there are significant outcome differences. But it looks more like 25%/49% to me based on the individual reports. (What tipped me off was his NLJ250 report (third link below) reported 280 2012 NU grads instead of 295 total.)
The question just before mine is relevant - why is BigLaw a must for you? What about a 60-lawyer powerhouse patent boutique?
If my only, only consideration was biglaw, I might consider NU over BC here if the differential was more manageable. I don't know what my breakpoint would be, necessarily. But it would have to be a lot smaller than 250K in debt (more, likely; actually unless you're getting some break from NU, its fully loaded current costs for new entrants is more like 292).
The problem with debt at that level is, even if you get that BigLaw job, you've entered yourself into a race to service what amounts to a pretty good sized home mortgage in the 6 or 7 years you'll have before they bounce you for not making partner (or the firm just downsizes again, whatever reason).
The rents are just to danged high.http://www.lstscorereports.com/?school=bc&show=ABAhttp://www.lstscorereports.com/?school=northwestern&show=abahttp://www.lawschooltransparency.com/tag/nlj-250/