I said that because it's usually a common thing on these forums saying cams and head work do bugger all. Obviously the money can be better spent on a bigger turbo, but at the cost of lag, not something every one is keen to do. Like i said, im not recommending Rob to do this, i just said it does do it's job when done right.
See my sig if you want to know what head work is done, can't be bothered listing it all.
Rob have you got a dyno graph with AFR's and boost? Maybe it just needs more timing put into it down low and a better boost controller.