There have been mixed opinions and I don't think we still have anyone who's got one.. yet..
I can hardly find information on any other forums but.. bumped into this article from a dealership in Canada;
http://www.dexterssubaru.com/NewsDetail02.asp?ArticleID=2724&OwnerID=&WebPageID=4749&WebSiteID=179
3/4 down the page you will see
"How SI-DRIVE Works" and
Turbocharger boost and AVCS operation remain unaffected with SI-DRIVE
Hmm interesting.. I'm thinking perhaps it's time to give it a go? That definately makes me feel a bit more confident!
C'mon Phil hurry up!