I know all the obvious ones, p+p/smaller pipes/ceramic coat etc etc

Im more interested in aftermarket boost controllers or external wastegates?

Iv read how an aftermarket cotroller (avcr) can make boost come on more rapidly than the stock oem control ? I gather the bigger boost solenoid has something to do with it?

What advantages/disadvantages will it give me if i welded the internal gate shut and added a 40mm ext wastegate?

any1?