In FCP, how much faster is a 2.4 quad core MBP than a 2007 2.4 C2D MBP?

[hal]

I've got a friend that crunches HD video in FCP (the last version before the total rebuild) in 10.7 on his 2.4GHz 2007 MBP maxed out setup, but it is slow going.

Is considering a massive jump to a late 2011 2.4GHz MBP with 1GB ATI 6770.

I'm sure that this thing will do this work 4x faster at the very least... anyone with hands on experience have a better number??