i have one each SS and Poly Chugger, in my set up, the Poly primes better, and runs better overall.
The SS works, and I didnt have to be as carefull installing the valves and fittings, but then, as long as you do go Ape on the poly, ou shold be fine, If they made a center inlet poly, I would be all over it, but they dont so as it is, I am stuck with one of each, but if I need to replace the SS I will go with poly this time
T