An Fcd and fuel reg will be fine mate to have it set up basic on a rolling road then at least u can make sure all your fueling is ok through it's rev range but its not ideal as the Fcd only tricks the ecu to stop fuel cut but can be done. Something like emanage blue would be the better idea for the long run as u can have it mapped to your exact set up and with be able to map it alot better and adjust your fuel field a lot better to run .9 or a bar of boost with management and u are also future proofing when gettin management as u can just have It re-mapped again to run a td04 efficiently and safely hope that helps mate The Fcd itself mate won't stop u over boosting or boost spiking that is down to the actuator and even a hks actuator can creep mate after a while and pending on how the cold the air is its just something to keep an eye on when giving it a foot full