Can someone tell me if there are any differences between sti and wrx cast oem headers..?

Also, do they differ from say 02>05 (ie uk newage)..?

Looking at having a go at some diy porting for my 05 wrx and been offered a set of 02 sti headers.

Thoughts welcome.....

 

I've never seen any difference in the ones I've ported.

Nick