I'm fine with a spec tire for USGT, however, I would be very disappointed if they are only available in 24mm widths. I used to run that width (Advans) and was always disappointed with the options I had, i.e. no where near the options available for 26mm tires.
I think it'd be great if the spec tire is available in 24mm and 26mm widths. Could be a fun tuning aid.