Nice choice. I do have a TTE600 unit in stock.
See here for info and few dynos : https://tteglobal.com/audi/rs3/8v.2-2.5-tfsi-daza-dnwa/402/tte600-race-evo-2.5tfsi-upgrade-turbocharger?number=TTE10400.3
TTE720 UPGRADE TURBOCHARGERS
Introducing our TTE720 Upgrade Turbochargers for the 2.9 TFSI fitted to RS4 B9 & RS5 and other Porsche models. The ultimate blend of power and response, and Plug&Play ease of fitment. Our first upgrade step utilizing the original turbochargers for greater flow...
Can use oem injectors and a 165bar fuel reg valve as many have done this but yes also can use other options and injector is better .
Its sold as plug & play fitting turbo and really just needs stage 2+ mods and custom map
Most report no loss in low down torque or ever say is laggy most...