<p>Sounds like a popularity contest: these schools have relatively little in common except being reasonably to very well-known. They range from urban (e.g. Yale) to suburban (Stanford, Princeton), strong undergraduate emphasis (Princeton) to little undergraduate emphasis (Harvard), academically top flight (Yale) to academically so-so (Brown). Figure out what you want from your education and you may find that your list changes. That said, if you are happy you are unlikely to be poorly served at any of the above.</p>