I doubt they will wear anywhere near as well as the commander II's. I've currently put on about 6k miles on the rear commander tire and I see minimal wear. It's still relatively round as well. I think I'll get 12k-15k out of it if they keep wearing like this. One of our trips was the same as the one that ate the Shinkos in 3k miles with an additional 3 days worth of touring in the mountains.
I bought the commander as a reaction to the short life I got from the rear shinko and they do wear like iron. Downside is there is quite a bit less grip. Not a problem in normal riding at all but with our insurance costs I only plate one bike at a time. As a result i end up sometimes going into the twisties with my Sport Touring riding friends (Ducati, VFR, etc) and I have to push the goldwing really really hard to try to keep up. This is when I notice the difference in grip between the Shinko and the Commander II. With the Shinko I was hitting the limit of the chassis, with the Commander it's the tire starting to let go. It's not something I notice in normal riding.
Once the commander wears out, which could be a while, I think I'll try an Avon Cobra in the rear to match the one I'm currently running in the front. It won't wear as long as the commander but does have more grip. I wish there were more tires available in these sizes. Id love to try Bridgestone t30 evo's in the GT version.
For those of you running tire shmoo/balancer/sealer. How big a mess is it when you change tires?
Jorg