Right guys I'm looking to learn some more about my engine.
I don't know any engine codes beyond k03 and k04 for the turbos so please forgive my novice tongue.
I'll start with my (possibly incorrect) beliefs.
The Mk5 engine with k03 was around 200 hp and a stage 1 went to 240 hp
The mk5 engine with k04 was around 230 hp and stage 1 went to 270hp
the mk6 engine with k03 is around 205 hp and stage 1 has taken mine to 270 bhp.
What has changed between the mk5 and mk6 engines (with ko3 turbos) to allow such a difference in remap potential?
The rollers you went on require re-calibrating

Rolling road days regually held here, as an example. Though no mk6's in the gallerys.
http://www.jkm.org.uk/performance/GalleryRollingroad.htmStandard mk5 GTi after remap 235-240
Edition 30 with K04 after stage 1 270bhp
Mk6 GTi after stage 1 around 250bhp
add Cold intake and full exhaust to see another 20bhp on average