I'd say the best part about Amherst is its terrific academic life. Professors, though spectacular and often world-known in their field, know your name, classes are small and participation is often lively, there is a lot of opportunity to do independent work with close individual attention from an expert in the field, students often take conversation from class into the dining hall and dorm room (making the school a 24/7 learning experience), and though a small school, by virtue of the Five College Consortium, virtually every class one would want is available!
My department in particular, Political Science, was phenomenal. There's a good balance between political theory, international relations, constitutional law, history, political economy, etc. The professors are often extremely accomplished. Bill Taubman (specializes in Russia) is a Pulitzer Prize winner, Austin Sarat (constitutional law) is one of the five most cited public law experts in the country, Hadley Arkes (political theory) is the architect of the Born Alive Infants Protection Act, Ronald Tiersky (European politics) was a State and Defense Department consultant. However, despite being so accomplished, the professor are accessible and phenomenal teachers as well. I've gotten to know several of my professors well outside of class.
I think Amherst's lack of distribution requirements and/or a core curriculum allows one to get breadth in a variety of disciplines outside of one's major. By virtue of the open curriculum, I was effectively able to triple minor. I took many courses in economics, philosophy, and music. Hence, I became very intimately familiar with textbook economic theory. Before school, I couldn't interpet the Wall Street Journal. Now I read it almost every morning with a great foundation for understanding. Before school, I'd never heard of Kant or Hume. Now, I've closely analyzed everyone from Plato and Aristotle to Kant, Hobbes and Locke to Rawls and Nussbaum. The journey through the Western philosophical tradition has made me reflect differently on many decisions, including career decisions. Finally, I didn't play instruments before school and now I'm a proficient guitarist. In many ways, the open curriculum let me quasi-quadruple major.
Though professors greatly contributed to my intellectual development, fellow students who also loved the material made me reflect on the material more closely and improve my understanding. These discussions ranged from debates with students over whether the US' hand in mediating the Israel-Palestinian dispute would be improved or not after the 1st gulf war, whether utilitarianism can be made compatible with our moral intuitions, whether allowing college students to sell stocks in themselves would made economic sense, and instructions on how to best voice a certain jazz chord on the guitar. These conversations were all spawned by coursework.
As you can expect from that explanation, many students at Amherst appreciate learning for its own sake. However, a very large portion of the school doesn't value its education outside the benefits it will yield in Wall Street, etc. The open curriculum allows students to pursue their vision of what a proper curriculum should be--pre-professional or an intellectual odyssey.