Torsion bar grommets?

[RUSS74GHIA]

I’m about to upgrade the torsion bars on my Ghia. It’s a ‘74 with 26 9/16” bars.
I’ve heard that the red Eurethane ones start well, but deteriorate quickly. There appears to be 2 types of rubber available- Stock & uprated. I’m leaning towards the yellow Delrin ones.
Can anyone give any advice or recommendations?

Car should be running low 12’s

[leec]

I used NOS German ones on the oval.

[Dalland]

Delrin/delron/POM is better than polyuretan, less noise, better self lubrication and stronger. But it is more brittle so dont use it anywhere. This place is okey. I made some my self since most of those you can buy is a bad fit and pom is very cheap!