I have a TI-84 Plus, and had a TI-89 Titanium.  I never used the TI-89 despite its feature set because it wasn't reactive.  I like to turn on the calculator and immediately start entering data, and that wasn't happening with the TI-89.I see there is a newer version of the TI-84 (CE Python) and I wonder if it handles more like a TI-84, or like a TI-89.  Are there any other (modern, and preferably rechargeable) calculators that I should consider?