All turbo kits are like that. There are only a handful of companies in the world that actually make turbos. Mitsubishi, garret, trubonetics, are just to name a few. HKS, Greddy, APexi don't make their own turbos, they just modifiy them to their specs and put their names on them. Greddy deals with mitsubishi turbos, HKS with garrett and so on.
So it's not as big a deal as one may first think.
Greddy, again, doesn't produce their own injectors, that is another part that is only made by a handful of companies.
No worries on that part.,...