Am I the only one that would prefer a HP 42s? $300 on ebay? are you kidding me? I know, I've got "RPN Calculator" on my android phone, but it's just not the same.
I love my 42s. It's still running great 24 years later. The Free42 app does a nice job on iPhone.
I haven't used a 42s, but the 50g is an excellent calculator and I used it quite a bit in college. I did lots of work with matrices and it is by far the best calculator I've ever used for that purpose.