The shire set is cutting it close, meaning that it's about 50% chance of sucess while the melded i250 with soph wep is about 30-40 DPS above the point so something closer to 70% success.
As for DarkerOrange's using the stats posted on lodestone we get 165.5 seconds to kill the A12S dummy, add some delays due to ping and 12 seconds is quite reasonable.
