I've been running BT45's on just about every bike I've had over the last 12 years, at the time I started using them I was running expensive Metzlers on my BMW R100RS and it was fine until it hit a white line or road irregularity, when it would just wander all over the place.
The BT45's were fantastic by comparison, so I kept using them, and have recommended them to everyone who's asked, but over the last 12 years I've had bikes (CB750's and Suzuki GS1000's) fitted with Dunlop, Michelin and Metzler tires, and to be honest, they've all been good. I get around 10,000 miles from a set of BT45's on average, but I imagine most modern tires would offer comparable mileage.
I see that Michelin is offering a new touring tire that promises twice the mileage of any comparable tire, if they sell them in 240 widths, I might buy a set for my Triumph Rocket III, the last thing I want to be doing is shelling out for a new set of tires (around 500 bucks a pair here in Oz currently) every 10,000 miles......... Cheers, Terry.