They are trusted by the city to serve the Pasadena Police Department's vehicles. They also give free estimates. It is a good idea to open an account at a California bank if you want to pay by check at any local establishment. There are quite a few banks within walking distance of Caltech. Many are clustered a few blocks north of campus on South Lake.
Undergraduates are also eligible for all sorts of loans.
There are a number of things to look for in a good bank. Choosing the wrong bank can mean money and hassle, so pick carefully. Reasonable hours are very important for Techers. Make sure your bank is open on Saturday. Make sure you find out whether ATMs you can use without extra charges are located conveniently.