Hello physics community, I am about to start my university studies and I am wondering which calculator to buy, a: TI-Nspire CX graphing calculator, Casio fX-CG20 graphing calculator or an HP 75mhz, 2300 functor, 3-1/5"x7-1/5"x9/10" graphing calculator. I simply want the best of the best, the one that has got better processor and higher versatility for resolving complex problems. May you please suggest? Thankyou!!!