Continental does not authorize their VANCO tires for the U.S. market. One of the biggest online retailers in the country says this about the VAnco2 tire
Wow what a stretch. Do you have a credible link to that little known fact. My Continental dealer would get a kick out of seeing that bit of myth.
Highway Rib Summer light truck tires are for drivers who want a combination of heavy-duty load capacity, even wear and low noise along with traction on dry and wet roads. Sometimes used as Original Equipment (O.E.) on medium and heavy-duty 2WD trucks, vans and pickups, Highway Rib Summer tires are not intended to be driven in near-freezing temperatures, through snow or on ice.
O.E. Highway Rib Summer light truck tires are typically purchased as direct replacements for worn-out pairs/sets of the vehicle’s original tires. They can also be used for other vehicle applications in complete sets of four or axle pairs if available in an appropriate size, load range and speed rating to match the existing O.E. tires’ performance category and specifications.
It's say nothing specific about replacing ST tires...nothing.
Nor does it say anything about P tires either but folks do use them on to replace P tires on their trailer and other vehicles that came with P tires.
And it says "Highway Rib Summer tires are not intended to be driven in near-freezing temperatures, through snow or on ice."
Big difference in wording of "not intended" or a "do not use".
The XPS Rib highway tire is a icon of what a free rolling tire is on a trailer. Its a poor tire to use on a truck in ice and snow country but works great on a trailer.
Your interpretation of the add is quite different that what it says and doesn't say.