I have to take issue with their marketing there. Columbus's Niobium alloy is the natural competitor to Reynolds 853. Both are about the same strength and are non-stainless HSLA alloys. The Columbus product that's closest to 953 is XCr which is stainless, super strong and expensive.

Those stainless alloys are actually stronger than you really need and they can't make them as thin as their strength would theoretically justify for practical reasons. So they're pretty cool but you will be saving as much weight by not painting them as the thinner gauges available are giving you.

Anything from Reynolds or Columbus is a quality tube and will make a great bike, as will double-butted standard 4130 or 25CrMo4 (which is exactly what Cromor, Zona and 525 are).