With your score, you're on the margins for the schools you listed - you will need the subjectivity of the process to weigh in your favor (i.e. an adcom really dig you based on your application for them to overlook your GMAT). It's not as much your quant score (since you're an engineer by background they are pretty confident that you can do numbers), but the composite score.
You have a competitive profile overall - I don't think it's going to be an issue for the schools you mentioned. If the quant was a "bad hair day" sort of score (you could've easily scored much higher given your practice tests), then you should re-take it. If you and the GMAT just don't mix, I would roll the dice with your score and focus on the applications.
Alex Chu
alex@mbaapply.com
www.mbaapply.com
http://mbaapply.blogspot.com