Corbins are hard as a rock, but there's a reason for it. Think of cowboys in the saddle all day on a trail ride. Now, have you ever felt how hard a western saddle is? Same principal, and for me at least, it works. I put a gunfighter and lady on my 05 1200/s and the difference was remarkable. At 100 miles the stocker was about done for me, the Corbin still felt hard and I was waiting for numb-butt to set in. At 200 miles, still waiting. 300, 400 and 500, still waiting.
I guess the best way to say it is that Corbins are not comfortable, but they don't cause discomfort or pain. Definately good for long haul riding.