To be honest, I wasnt impressed with the impeller design on the metal impeller pump I put in my car. The plastic unit I replaced had a significantly smoother profile and what appeared to be a higher efficiency design. But everyone runs the metal units without issue, not so much with the plastic unit. I just dont trust plastic components in my cooling system, the only plastic I have left is the HVAC system.
S52|ZF|TRM Coilovers 670/895|Staggered 18" 5's