Good info - cheers for the replies.
I never floor it in 1st; that would undoubtedly light the tyres up. Don't really do any 0-60 style driving, although 30-'70ish' is a different matter.
I've no issues with traction in 3rd and up - just occasionally lose grip going from 30/40 in 2nd at WOT.
I suppose the k03 delivery is quite punchy anyway so it's to be expected, with nearly 300lb/ft at low revs.
The Super Sports do a decent job, I think I'd be spinning up a lot more on the Kumho Ecstas I had on the previous wheels.
Already on H&R 30mm springs, so I'll definitely look at the Superpro kit soon, and probably front and rear ARBs.
I'm pretty much sold on the K04 conversion itself, I've heard nothing but good things. And from what I gather, the slightly longer spool over a K03 is negligable - it's still a relatively 'small' turbo.
Just need to stop spending my money on Peroni and sort some TTRS stoppers first...