The Trevala F rods are high modulus carbon blanks with a TC4 tip. Its a very crisp and responsive jigging rod. We gave them a little more backbone for the US anglers. The Game Type J rods are built with Spiral X and High Power X technology. Essentially they use one sheet of carbon and the rest is carbon tape. It cuts the weight of the rod and reduces excessive oscillation of the rod blank. So much crisper than a standard rod blank. These models are not for slow jigs. They are made for standard vertical jigging. They will work for those jigs, but not for the technical fishing style that they do in Japan with the slow jigs.
In Japan they do offer a Slow Jigging series in Game Type J (I think in Type J), but we did not bring these to the US. I do not think the US angler would like a rod that bends all the way through the reel seat like the slow jigging rods.
They're available in both. I own both. The conventional is a really thin diameter rod but powerful. I compare it to my Temple Reef Mythos Plus but not quite as refined. I'm surprised that the spinning model the blank is almost twice as thick in diameter. For the price I'd get a Terez or a Tevala type F.