I disagree... 8 is every bit just as lethal. Even has better turn rate. Nobody's using them for their rate of roll unless they're stick stirring these days.
As for high-speed dives, they seem to handle about the same to me. They have nearly identical power curves, rates of climbs, turn rates, killing ability.
The 8 actually has the upper hand, as far as manuverability AND range go, so it's probably the more lethal option when it comes down to it.
Can't discuss perking the 16 without discussing it on the 8.