The pista and super pista are entirely different beasts...one is for street riding, the other is for track racing. You can ride on the street and track race with either frame, but neither is optimal for both. Sounds to me like you really don't know exactly what you want yet. I would look around and not confine yourself to Bianchi....there are lots of other bikes that are somewhere in middle ground between these two frames, performance-wise, and cost-wise.

Also, as a general rule for myself, if I have to save a few months to be able to buy a particular bike, then that means buying it is probably not a fiscally wise choice. In this case it seems to me like you are intending to save a few months for a frame?...not worth it. You'll go the same speed with just about any frame.