I just put the BT021's on and so far I am very impressed. They have very good traction and combined with light and neutral steering characteristics, they are very confidence inspiring. I only have a few hundred miles on them so I don't know how they will wear. I have not tried them in the rain yet. However, of all the tires I have tried ( Avons, Metzler Z6, Perilli Strada, and the Pilot Road) so far I think I like these the best.
Back in dec. 1999, I had an ST1100 and tried all kinds of tires including the Metzler Z4, the Dunlap D205, and several bias ply tires. When I tried a set or BT020's I never use any other tire again. At the time they were clearly the best tire out there for that bike. Time marches on and the BT020 got a little long in the tooth so Bridgestone introduced the BT021 as it's replacement.
Southwest moto tires are selling a set of these for $215 delivered. Thats about 30 - 40 bucks cheaper than what they are selling the competing tires for. Not a bad deal.