+1
for reliability, keep it standard.
for modding, after usual exhaust, intake, IMO a boost controller is the best bang-for-buck. £160 gets you whatever boost pressure you turbo can give (but on standard engine internals, 1.2bar is considered max safe boost pressure). Going from standard (0.7bar?) to 1.2 is like.....well....hang on tight!:toung:
remember when modding, things will start to break. standard car, eg a head gasket is a bad misfortune. on a modded (performance) car things like that are a fact of life. just don't complain when something happens!