"Prussik" is a bit vague. Do you mean a taut-line hitch with 2-over & 2-under, or a true prussic loop, which is 3 over, and 3 under, tied with a continuous loop of rope?
There are several other variations that are called a "prussik" also.
I climbed for years on a taut-line, and I never used a Blake's enough to get comfortable with it, even though I understand that it is supposed to be superior. The old taut-line sure could bind up tight sometimes...
Given the choice, I think I would take a prussic loop, done 3-over & 3-under. Slides good, never binds too much, and it pretty much demands to be used in a split-tail system. Safer & smarter!