[drbawb]

I also learned on a TI-83 (handed down from my sister) and a TI-92 (from the boxes at school).

However, I much preferred my HP-50g, USER RPL was an absolute dream to program in, the USB interface was fantastic, an emulator was readily available, and you could even write applications in C and cross-compile them for the calculator.

That and RPN with a multi-line display and an [virtually] unlimited stack is the "one true way."