Spohn Arm Choices - Del-Sphere or just polyurethane?

[Eidolon]

So by now I'm sure you've all seen Spohn's 40% off sale post. I want to take advantage of this. But I'm not quite sure what to order. I know I want the pro-touring arms, trailing, arms, and toe rods. That's easy enough. The question is, which form of each to get?

My car is now a fair-weather driver, and I'll be participating in my first HPDE later this year. So I'd like for it to still be drivable on the street but perform relatively well on the track. So I'm thinking polyurethane for the control arms.

As for the toe rods and trailing arms, which makes sense? Polyurethane, rod-end, or del-sphere?

Thanks for the help, guys!

[Eidolon]

Got it figured out. I'm gonna go ahead and go with the del-sphere ends. It should be quieter and more reliable than the rod-ends, but without the binding issues of polyurethane.