Buy Now or Wait for Revision B?

[parisse]

The cheapest way to run giac on a calculator today is a TI nspire (*not* CAS, with OS 3.6) with ndless and khicas (this is a beta stage port of giac, more complete than on the Prime, since all synonyms are available, and it also has a few more advanced algorithms that I could compile with nspire-g++). The nspire CAS builtin CAS is not beta anymore, but its CAS is inferior to the Prime CAS and it is a little more expensive than the Prime.
The alpha keyboard of the nspire is very appreciated to enter commands if you know them. It is indeed difficult to write something on the Prime, because you must always lock/unlock the alpha keyboard, unlike on the 50. On the other hand, the touchscreen on the Prime is very useful.