Originally posted by rjl
I use Active tyres, similar rubber to Zac but much stiffer rim.
Oh! . . . there you are rjl.
Agreed, Active's have a much stiffer rim. It's likely the rim stiffness also contributes to the stability these wheels exhibit.
The other side of the coin is that it is possible to break them. We've broken a couple, but a bit of CA glue sees them back in service, just fine.
It's all a compromise. Overall, I'm happier to glue the few breaks than try and fix a wonky one - that seldom works for me.