Has anyone actually done this, or is this just hearsay?

 

I have done it and yes it fits just like the JDM one does.

 

Awesome! thanks, mmurray75!

Where did you get it from? Subaruwrxparts.com wants $275 for it, with no gaskets and no CEL fix.

 

I have no idea where the person got it. I just installed it for him.

 

I'm guessing you mean the JDM V8 uppipe, which is split for the twinscroll, right?

I'm asking about the US STi uppipe, which can be found here:
http://www.subaruwrxparts.com/per-wrx-drivetrain.html

"STi Uppipe
Catless uppipe as found standard on the STi models- does not contain an EGT bung. Only a discerning eye will be able to distinguish this uppipe from the one found stock on the Impreza WRX. It is highly suggested that you replace both uppipe gaskets when installing this product. They are available on this page, a few items above this one.

Price:$275.00"

 

I am going to buy one (STi Uppipe) this afternoon and put it in this weekend - that subaruwrxparts website is run by the dealer where I got my car (Exeter Subaru in N.H.) - I was assured by the parts dude that it was an exact fit but of course, no cat and no EGT (which I was told was no longer necessary w/ no cat) - mmboost, thanks for posting specific info on the EGT sensor resistor...I was looking through the threads to find out which one it was 'cause now I need one!