I think both Sasuke and Minato can be declared as the fastest characters in NV. The have almost identical speed, with only a negligible difference between the two if it really exists.
Sasuke's range is limited compared to Minato's (which is a mostly a non issue in battle), but his teleportation is far superior (which is important). Sasuke can move instantly to where ever he wants without a second thought. Whereas Minato can only teleport to a certain spot if he has placed a seal already (which he might not always get a chance to do). He will not necessarily be able teleport to a required spot at the required time, which is a major drawback. And moving only to places in the battlefield where his seals are already placed, can limit its usefulness at certain occasions and limit the number of places he can move, and that can make his movements can be much easier to anticipate by locating the seals and placing counter attacks in advance.
Therefore...
In speed:
Sasuke >= Minato
In mechanism of speed:
Sasuke >> Minato
In usefulness in battle:
Sasuke > Minato
In long distance transportation:
Sasuke < Minato
Yeah, pretty much summed up... And Sasuke's foot speed which is also incredibly fast (arguably the fastest among all S/T users), added to his S/T ability which is above all else, probably makes him the fastest person.