copy/paste from another post:
what i have found is that a low duro doesn't always equal fast wear, some tires have better rubber compounds that allow them to be softer but have better wear properties, the best example of this is the maxxis slow rizzay and super tackey, the ST is harder by 2a but i have found the slow rizzay wears better.
but remember that SRYs may not roll as fast so it could be harder getting through rythems where you can get a pedal in.