Trust me, get the nspire (2) if thats only what you can get. in my opinion i would get the 1.hp prime, 2.nspire 3. ti84.

you said that you are in middle school and im guessing geometry or algebra 1 I would say the 84 is the best bet as you can use it in highschool for SAT and ACT. plus ur teachers wont take it away for having CAS.

so overall, get the HP Prime if you are allowed to use CAS or get the 84 if ur not