I don't want to sound like a daft tw@t, but you have tried altering your amp yeah?
Like, I know pickups do a lot to tone, and if it doesn't work out it could very well be your pickups but changing is a big thing to do compared to just generally more tweaking and such. What are your settings on the Cornford?
And possibly change the pots like mentioned above.
Just my thought on this. It's like upgrading your car, yes a turbo does improve it but at the end of the day, better performance comes with tweaking after getting the awesome shiz to put into it.
Or I could be all wrong.
hey dude, yeah I have tried all the options as I like to tune every part of my set up.
I thought the same thing as you, went right through the whole set up (pup hight, gain, tone, valves, pots, cables, you name it) and still not feeling it when higher up the neck (it just turns thin)
so I think a pickup swap is the only way...
Will put these VHIIs in a more hot rod type guitar I think, put some fatter classic pups in PRS :)