Bank stocks were the last place any investor wanted to be during the financial crisis. However, as balance sheets have improved, bank stocks have gone on an impressive run. Despite the recent gains, many of the big banks are still trading at deep discounts when compared to their historical valuations.

In this video, Motley Fool banking analysts Matt Koppenheffer and David Hanson identify which banks are the cheapest and debate how much upside these megabanks have over the next five years.