Who has used either of these in a California T? Both of these are done with a harness. VR Tune seems very in expensive. I have read threads that talk really badly of modifying the ECU, but it did not sound like any of them actually installed one. Talk of "a friend blow an engine". Hoping to here from people that have installed. Any issues? Any noticeable improvements? Do you add/remove the ECU that is piggy backed on? Thanks.
