It's a fantastic option, I'm at work so i can't find the video, but sound performance tested a BW S3xx against the 6266 and the 6266 made more power, but the BW spooled up better.
On evom the supporters of BW stuff agree that the spool and transient boost with the BW turbo is superior to PTE but in sacrifice for max power.
I'd say get the BW stuff and not have any doubt about the turbo eating its face, worth the 30-40whp you might give up.
I'm just not a fanboy of it as I haven't seen anything but market hype for the ETT and EFR stuff.
http://www.spracingforum.com/forums/...ESTING-RESULTS
http://www.youtube.com/watch?v=iVqiUhAv01c&hd=1