hhmm . . . then in this case, I find it more practical and cost saving to get the MK5 GTI instead of the MK6.
And also as some have also mentioned that the MK6 is merely a facelift of the MK5! Although some slight adjustments like a better fuel pump, 10 more BHP (which IMO i find it ridiculous) and a little change in the design of the front bumper!
Can k03 be swapped for the k04 turbo?
Any adverse side effects expected?
Because if the Edition 30/Pirelli uses a k04 turbo and the rest are kept the same like the Standard,
then,
Wouldn't be the "same" if I had the Standard, But swapped it for the k04 and do a remap?
Yes a K03 to a K04 is a relatively easy swap compared with going big turbo, but you would need quite a few bolt on bits 
I'm guessing this would include, injectors, ignition, FMIC, DV? and not forgetting the remap!?