All three of those tires you linked to have a 'features' description at the bottom of the page, each refers to 'latex or butyl tubes' so are these tires clinchers or true sew-ups w/tubes inside? Do you get to specify what kind of tube you want when you order if sew-ups?

I'd have to believe a company selling tires would be careful about ambiguities in their ad copy. Important to describe a product carefully otherwise have to suffer slings & arrows from disappointed customers.

I'll post what I hear back from ExcelSports about these questions you and I have; seems they're closed until next Tuesday so we'll have to be patient.