Hypergear use Garrett ball bearing cores now, their latest RV1 is a GT2971and I've got their RV5 which is a GTX3071. I've driven Stao's Stagea (hdi cooler, pod and exhaust only) with RV1 high flow, that felt like a stock turbo with bit more power, no boost creep.
Mine's cutting out at 152awkws, You will need front mount cooler, injectors, exhaust and piggy back ecu for 200awkws.