I have tried a couple of Greentyres which are similar. The size that was described as a 23mm 100 psi equivalent was ok except, as Dobber suggests, it is a bit of a hard ride. When that one wore down I tried a wider version, either 32 or 35 mm, 85 psi equivalent. The first ride I thought my legs were really tired. During the second one I realized it wasn't my legs but the tire. Picture feeling like you are riding on rain-softened ground or pedalling up a slight incline - all the time. No momentum at all, just constant effort. I snatched it off after that second ride and probably threw it away. Makes me shudder just thinking about it. As I said, though, the narrower, firmer one was tolerable. I just decided I could manage almost as well with thorn-resistant tubes, Tuffy liners, and kevlar belted tires.