Bradley is a small, easy to deal with airport. No traffic, no tolls. I would look at airfares, nonstop vs transfers, car rental rates at each site, and take that into account. Might make sense to fly into one airport, out of another. If you can do a 4 to 5 day trip to see 4 schools, that would be best, since theyre not close to each other. southwest flies out of bdl and boston. Has one way fares. Umass is only about 40 easy min drive north of bdl. So maybe do this one first or last, and fly in or out of bdl.