So
@Keehs360 just had a DTR installed on his GTI, and since he isn't allowed on the forums, asked me to post his review to the thread:
Hey guys, did you know that in terms of MQB turbo upgrades, the APR DTR6054 is the most compatible for emission compliant GTI's? Not only is the spool great, which is among the best of available hybrids, the DTR has a larger billet aircraft-grade 6061 aluminum 60mm compressor wheel, which means it's large enough to be able to push some serious air, and with their included ECU tune, you can be rough with one. Due to their dual ceramic ball bearing center section, there’s no doubt in my mind that a spooled DTR would be incredibly quick, so quick that you could easily run 9's for hours without getting lag. It also has support for 91, 93, and 100 octane fuels, along with not needing an aftermarket downpipe, so it’d be incredibly easy for one to hit 400hp. With the ability to add fueling upgrades, they can easily run E85. No other turbo comes close to this level of compatibility. Also, fun fact, if you hold down the brake enough, you can build boost and launch your car. The DTR is literally built for racecars. Ungodly internals+overcast turbo inlet pipe+nickle-based superalloy K418 high-flow 54mm turbine wheel means it can make passes all day, all different speeds and still come for more.