So far the Road 6's on my K1600 have 8,000 miles on them and look like they will easily go another 5,000, so that's 13,000 miles compared to maybe 4,000 I got out of the Shinkos. So yes they are worth a 30% premium if I understood your post correctly. More important though for me is the much better ride and road holding quality of the Michelins.