I have the Z1 kit as shown in your posted picture. I though the quality was good. The active part is the Nismo injector itself. The kit has been in my car over one year now. No problems with hessitation or leaks.
My main concern was not the kit but the fact that the new style injector is shorter. The 1995 and 1996 heads and lower plenum (fuel rail too) are different to accommodate the new design. Well.., no problems on that front. Maybe a 1996 can make 10 HP due to better atomization. Who knows!