My gut says Brown. I certainly don’t think rankings are the be all and end all, but they can help to give a sense of where a school stands relative to other institutions – in this case Brown is ranked above WPI for engineering by a good bit (44 v 87). Brown’s rank for engineering is right on par with some fine engineering programs such as Vandy, Lehigh, and ND (to name a few) plus Brown has an overall reputation for attracting exceptionally smart students. I would imagine that a solid engineering student would have great opportunities coming out of Brown. But you should do some legwork. Have you tried to get information from the two schools career placement office or engineering dept. about what firms come to interview, where graduates get jobs or go on to grad school?