Continental Ultra Sport II on pretty much any rim. I started toting a Kool Stop bead jack in my jersey pocket or seat bag every ride, and heavy duty plastic tire levers to remove them.
Eventually I retired the Ultra Sport II tires to indoor trainer duty. Good tires and excellent value, but my aging arthritic wrists and thumb joints can't handle stubborn tires anymore. I switched to Conti GP Classics for most road bikes, and Some Supple Vitesse for my go-fast bike.