Fast prime in the old days even meant f4.
f2.8 and below are certainly considered fast primes, don't need to be f1.4
Anyway, Sigma 30/1.4 is nice. Fast and center sharp, which can add to apparent sharpness. However, it is never evenly sharp, so for stuff than needs more even sharpness (eg. detail work, landscapes), not as ideal. Not as well rounder a lens imho.
DA35/2.4, very value for money. Fast in most respects, even sharpness and very sharp from wide open. Downside is its f2.4 or course compared to some other options.
DA35ltd/2.8 macro. Very nicely constructed (ltd quality). Macro, which can be very useful. Walkabout and take photos of normal stuff, see nice small things like flowers, just go up close and shoot them. That's its advantage.
There is also the FA35/2, the slightly faster brother of the DA35/2.4 and one of the best primes ever made (said by Mike Johnston of the Online Photographer... not me
) the FA31ltd .