Hi;
I have both (one of each) and in terms of 'worth it', I think the HP50G would be the choice because:
it accepts SD cards to increase memory capacity (my H50G has a 1GByte SD card...).
upgradable operating system, meanning that bugs are ellectable to corrections.
more lines in the LCD; somehow you can use it to show more data.
more user RAM in the basic configuration; a bit more than 1MBytes (377KB RAM and 780KB Flash ROM available to the user, according to the HP50G datasheet).
About the HP48GII. It has almost all algebraic and math features available with the HP50G (CAS, equation Library, etc), but it has about 81KBytes RAM (80.7KB available to the user, according to the datasheet). If we consider that it has a lot of built-in resources, user RAM may not be an issue, I guess.
As a final consideration... I actually think that the HP50G has a better look, with black finishment. It is closer to previous, successful HP calculators, indeed.
Cheers.
Luiz (Brazil)
Edited: 23 May 2007, 9:42 p.m.