rb30et would be a nice motor in the zed and bolt on mods are plentiful due to the vl's. But if I were you, looking at the car as a daily driver, you would get good power and awesome fuel economy out of the rb25det. I have both an r32 and r33 skyline, and the power difference is huge, especially when boosted, but the fuel economy is similiar. So my vote would definately be with Scott and the rb25. You could also get great streetability out of a stock rb26dett, but they can get quite thirsty on fuel.