Yeah, I dunno. Where I live GKs are often recommended for gravel, but at the local Gravel FB group I often see ppl complain about them flatting all the time, however not often specifying what particular model. Cant say I tried any of them but I agree. The "slick" model, without the "+" moniker sure look like any ol road tyre, except maybe for the claimed anti-flat casing that doesnt seem to do much anyway. I do think they are less susceptible to side cuts than true road tyres like GP5000 tho. Id agree the standard slick is as much (little) "gravel" as a many slightly reinforced road tyres.