in my opinion mate for 150bhp the zetec is the best option cus its n/a and has instant throttle response from low revs rather than lag etc but once ur 20/21 etc u'll be bored of that and want more power this will be expensive on a zetec but 200bhp+ is relatively cheap on a rs turbo lump
if u only want 150bhp for now ur engine will be very reliable aslong as its setup right cus 150bhp is easy power for a rs turbo engine so not many components are under alot of strain causing them to fail