take the vx the vs has already been worked to its tits if its a 5litre
you can do alot with 5.7litres can get them pushing 300kw with just a tune.......
my vt r8 is 250kw stock,
parramatta automotive in Sydney can do a maffless tune to get it pushing 300kw,
with a minor air pipe etc and stuff all included in the price of $1000