I've got (4) freeway days (337 miles) on the Bridgestone S21, (190/55) tires...and already down to about 1/4 " of side "stripe".
I removed Michelin Pilot 3 (190/50) tires. I've run the various Pilot tires on several bikes and have been fairly happy. But putting them on the EBR was not a good move. Don't know whether is was the Pilot 3 design, or the combination of that tire on that bike.
In comaprison to the S20...the Pilot 3 tires are harsh riding, follow "every" groove in the road, from rain grooves, to open expansion joints, to sealed expansion joints to cracks in the concrete. Just not very inspiring.
Decided to give the Dunlop, "Qualifier" a try. Got to my favorite tire dealer and noticed the S21. I talked to one of the guys about them...he talked me into the S21's.
If you want a tire that's smooth riding, not kiddish, and doesn't follow the cracks in the road, is smooth in the side to side transition, and leans with confidence, you might like this tire. Note that the overall S20 traction seem's at least, slightly better than the Pilot 3's also.
Though to be fair, this tire is a 55 vs a 50 series and I also dropped the forks a tad, so the turning is smooth and easier than before the tire change. So the combination of the tire design, the tire height and dropping the front...it's a different (read that, BETTER) driving bike.
Mike