I had an older version of the Flintridge, but they were aging so I bought the Pro GCT version. A big upgrade, with good puncture protection and 120 tpi casing. I used these with tubes on an '80s steel sports tourer restomod, for use as an all-road / gravel bike. The tires roll very well on pavement even at the moderate pressures used off-road, and they are surprisingly capable on more technical terrain. I managed rocky and rooty singletrack without any punctures, and they are surprisingly grippy in sand. Hard to imagine anything better for the price, a good compromise between performance and robustness. Would definitely recommend.