This assigned rating is one star for my HP 12c Platinium which describes this calculator's value for my purposes - to make the calculations required for "Buffettology" by Mary Buffett & David Clark. The 12c comes with a Quick Start Guide and a disk which enables the downloading and printing of a detailed manual. The types of financial calculations covered were cash flow types; investment decisions and their keystrokes were not covered. "Buffettology" incorporates a Texas Instruments BA-35 Solar financial calculator. For the types of financial calculations described in "Buffettology" You should purchase the Texas Instruments BA-35 Financial calculator to save time and for ease of use.