I wish there were UTQG ratings for motorcycle tires. Then we'd have some meaningful way to compare these tires.
Terry, when you say "best", do you mean longer life (which some would call better), or better performance, grip, traction (which others would call better), which are usually mutually exclusive.
G'Day Mate, none of my bikes do big miles except my Yamaha FJR1300, which of course is fitted with Pirelli's too, in it's case though, Angel GT's, as they don't do Sport Demons for FJR1300's. Anyhoo, I don't care about longevity, there aren't too many owners of SOHC4's that do big miles nowadays, so my opinion is based purely on "better performance, grip, traction" etc.
Tyres have a "Use By" date, so quite often when I buy a bike (I've bought 7 bikes in the last year) I'll replace the tyres with new ones, regardless of how good they still look. I replaced the Michelin tyres on my VFR750 with new Michelin Pilot Road 4's last month, the tyres that were on it still looked okay, but were probably close to 20 years old? Also, nothing feels better than a new set of tyres on a bike, quite often a bike's poor "Handling" can be traced to the age and condition of it's tyres.
One problem with BT45's that I discovered, was that the front tyres would "scallop" after awhile, and because I always replace my tyres as a set, I'd have to throw away a perfectly servicable rear tyre due to the scalloped front. No biggie, but a little annoying too. Cheers, Terry.