No big differences between PWG and EWG turbos, not worth it. Tuning, I recommend:
MHD tuning (
http://mhdtuning.com) Stage 2+ E98 flash
Catless or racecat DP
BIG intercooler
CP
Enjoy
edit:
my results
0-100km/h (60 miles)
1/4 mile
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530e xDrive LCI and
DCT, MHD Stage 2+ E30, xHP Stage 3, catless DP:s, NGK F8S
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