It seems the problem with the ESI is you can't make it go fast for less then a comparable TSI, or GST.

You could turbo the 420A but then you're pretty close to maxing out that engine without tearing it apart. Even if you went with forged internals you would be (in my opinion) wasting your money on some turbocharged hybrid neon engine that just now after thousands of dollars on par with a stock TSI.

That leaves an engine swap...the 4G63 engine swap is very possible, but when you're done you still have spent way too much money on a stock TSI.

Nicks 2.5L TT V6 idea sounds like much more fun you should just do that.