The debate goes on - I contacted Subaru about the Type Uk when I was first buying mine due to all the different opinions, I was advised as Pete said it was a dealer STI fitted PPP upgrade and a model in its own right so insurance wasn't impacted as its a dealer car - This model is also referenced on the Subaru Impreza Wikipedia page
Either way you are not getting a bad motor - the standard STI is easily upgraded, the 330s has all the good stuff plus some nice tweaks. Feedback I had from friends I let out in mine who had owned previous Imprezas was the steering was not as sharp, this has been sorted with the new Impreza but can be addressed with kits from people like Litchfield