Interesting. I don't see anything about additional travel, though.
It also isn't clear to me that it's a proper cartridge setup: the compression side is (and apparently uses a shim stack vs the coil spring that RaceTech etc use), but the rebound side is unclear to me. It sounds to me like it has a GVE-style coil spring for the rebound side, but I could be wrong.
In comparison to cartridge kits for other bikes, such as the Traxxion AK20, the price is significantly lower.
poking around on their web site https://rppmoto.com/rpp-moto-c4-damp...nc700x-nc750x/ is the option with extra travel (and it's due to extra ride height). That'd be a nice option to see on my NC. If I didn't already have GVEs I'd consider this.