A lot of my mates are big ford boys running big power and very rarely do I see them use dv's just full on chatter when I was ct9 I had a hks dv then took it off and had chatter and didn't notice any difference in spool time and now td04 at a bar and I hit boost at 3800 rpm everytime no dv I think it's more down to the personal preference of each person and what they want hear