Purchase advice questions

[SalivationArmy]

Are there any models that are not neutered for school/testing use?

Since I am not in school and facing testing requirement I am wondering if there are any models that are better than their school oriented brethren. TI models are hardly more than glossy version of 80's tech. I think someone held a gun to their heads to get them to upgrade their screens.

I intend to start learning again as my son is entering high school this fall. I want to be able to help him get into the higher maths. but I also want to explore on my own outside of the typical education path.

i've looked into:
ti-92 series - old, but interesting

ti-nspire, got one, hated it. (not in same class as other here I know)

ti-8x, used many but only one I liked, just cannot remember which it was. fading memories.

HP 300s - no rpn as far as I could tell. non-programmable.

HP 35s - new yet old. but has RPN. programmable i think.

Casio fx991ex - seems to wipe itself everytime you turn it off. Non-programmable. FAST though. This is just what I was reading.

Sharp EL-W516XBSL - lots of built in functions (552 I think) but gcd missing in all but the german model which has nearly 100 more functions. I hate that you cannot get a full featured model in an english language because of school requirements.

HP Prime - I have considered some of these full graphing models, but my experience with the nspire has turned me off. How much does the expanded abilities this provides get in the way of lower level usage?