It is pretty funny really as in the last 2 years I have been involved in a very very large German OEM manufacturer (bigger than BW) that had pre-released a "product" that was really still a prototype. And man was that not the biggest cluster for our company! Product failures, and failure to supply... then in the end they would not supply because they knew the product was so bad.
Anyway, as I understand it these turbochargers were designed with special care as far as turbine and compressor wheel matching and turbine housing sizes. Is there still a necessity for a surge ported compressor housing? Considering it does take a bit of efficiency away at the top end. Or was the decision to port the housing done as a precaution?