I had a set of the Michy Road 6 GT's on my K1600 GTL and they just never felt "hooked up" to me. Prior to the Road 6's I ran Pirelli Angel GT II's and those felt absolutely nailed to the tarmac. Loved them. Mileage sucked.
I am currently riding a GSA with the Pirelli Scorpion Trail II's and I agree that they stick like glue and give a lot of confidence in the corners and the wet. So far I have about 3500 miles on them and the rear is starting to square off (what can I say... With a few exceptions, I haven't found many roads in Florida that aren't pencil straight). Plenty of life left in them. I may try the Continental Trail Attack 3's next as I hear good things about them. I also know a number of GS and Multistrada riders who fervently LOVE the Dunlop Mutant's and don't understand why I haven't tried them, and they say they get great milage out of them. You may want to look at those as a potential option.
So far I really like the stickiness of Pirelli's but haven't run across any that last long. Make sense though, softer more stick, whereas the Michelin's are hard and give you high mileage. YMMV