Question
Using the definition $$ \text{sf}(x) = \prod_{n=1}^{x} n! $$ Where would the Superfactorial ($\text{sf}(x)$) sit on the fast-growing hiearchy?
Context
The reason I am asking is because recently I have been pondering, which is faster growing, the hyperfactorial ($f_2(f_2(x))$ on the fast growing hiearchy), the exponential factorial ($f_3(x)$ on the fast-growing hiearchy) or the superfactorial?