[slotloco]

Yes, sidewall lettering - and yes the surface seems to degrade very quickly as in 'balling up'.
Thanks for all the info' but I think they're just TOO soft.

If you are keen on experimenting, and based on what I've read about what works on your Sport tracks, I would be trying either the HiGrip wide medium - very last line in the chart
- or a Pro-speed Wide "hard" 28 shore, which is closer to a P6