I also have a vg30 turbo with r33 hi-flow front..Dont know much about it but it made 235rwkw at 10-12psi.
Ive recently converted the car to manual and taking it back to get retuned..
This turbo comes on really aggresive i love the feel and shove it gets, cant campare it to the stock turbo. Midrange couldnt really be tuned as Im only using a safc.
theres some old threads about this combination of turbos if yous arn't aware, that person had great results also.
Cheers