my mate has one on his starlet on stock motor with a custom inlet on running just under 1.1bar and is making 252bhp but what he has told me is if it was not for the inlet it would prob be a bit more laggy. as he has tried a vf23 a tdo4 and the vf28. the vf28 making the most power but the td04 been a lot more responsive and for the vf 23 it shit it self because of a boost leak. but do not take it over 1.4 bar cause the vf28 will shit its self. all the vf ball bearing turbos are only good for 1.4 bar