GM Smerdon's book on the Scandinavian is what rekindled my passion for chess a few years ago, and for the first time made me want to actually study the game. I enjoy his views on of practical chances vs. engine objectivity, and his results-based "part time grandmaster" approach. So it should be obvious what my recommendation is.
(Hint: it starts with "P"...)
(and ends with "ortugese")
know not much about the nf6 scandi but im intrigued now maybe i check out smerdon