Newbie - my strong reccomendation to you is to come to a Sydney meet and sit in the passenger seat of a car that has mods you're thinking of.
That's one of the only ways to understand all this experientially
Lag is one overrated bit of crap - even Scott from insight said my car is too laggy
I think its fine - makes 1psi at 1900rpm in second or third gear, and 14psi by 2800 in third without proper tuning and this is with a rich mixture and minimal timing
If you have an auto, its easy to kick back a gear and get into boost
From all accounts, vf52 is a decent upgrade for moderate power without much lag at all - depends on how cheap you get one for as to whether its worth it
Come to the next Sydney meet so u can figure it out
Mick