I've run UHD tubes for over 60,000 miles on the 990. Never an issue and I have run plenty of extended triple digit speeds on Mexican Cuotas. I use baby powder when I put the tubes in. Probably doesnt matter. The UHD tubes have saved me plenty of flats in higher speed desert riding IMO. I run 25/25 psi off pavement and off road, then 34/40 psi for extended pavement days.
I really dont see an issue with them, but that's just me, YMMV.
Riding the Americas: No Fumar Espaņol