So, for a budding math student ...

[jebem]

Interesting discussion here...

If the goal is to have fun and learn/refresh mathematics, no matter your age, then HP-Prime is excellent, specially because it has a few "issues" that I hope to see fixed by HP along the way.
We can learn a lot when facing "issues" and investigate to understand what is the root cause of them.

Me? I have one HP-48G+, one HP-48GII, one HP-49G+, one HP-50G and the Prime, just to mention the more recent ones from HP. I also have a bunch of good CASIO and TI machines to compare against HP.

Currently, I keep the 50G side by side with the Prime on my home desk, and it is fun and informative to compare how they answer for the same input.