Have a 14 year old TI-89, that I still use to this day. It's small, simple, quick, and have all the functions and symbols I use under the custom menu. Amazing t

Have a 14 year old TI-89, that I still use to this day. It's small, simple, quick, and have all the functions and symbols I use under the custom menu. Amazing their haven't been any screen and function improvements (built in programs).