RPN is nice, but I find textbook mode better

[TheKaneB]

I agree on the textbook mode of the Prime.
The integrated formula editor and the touchscreen make it very easy to enter complex formulas, and the template system reduces the amount of parenthesis used by older algebraic calculators.

On the 50G however, the equation writer is a separated app and I don't like the user interface, where you have to select portions of the equation to apply operators in a non intuitive way. Therefore I prefer the RPN / RPL entry in that case. On the simpler scientific model I find RPN to be absolutely the best for my taste.