I'm up in Colorado now, so I know for a fact that I couldn't do it, hell at Bandimere (5800 ft) up here I'd be lucky to run a 14.6 lol. Although with an experienced driver who's car pulls around 99mph trap speeds, with a 1.7-1.8 60ft time, powershifting at the right rpms I honestly believe a 13.6 or better is in the cards. Granted it would take the right track conditions ie altitude, temperature, humidity, track prep, the higher the octane fuel the better (I've heard our cars are very picky, and cut boost if octane is too low). Most people don't powershift at the track (hold the gas to the floor while shifting), which I don't blame them in an AWD car, as it could possibly damage the cars drivetrain, however in my experiences with previous cars, powershifting has knocked off .2-.3 seconds in the 1320.
There was a guy over on Nasioc a few years ago, that ran a 13.7 in a bone stock 02 WRX. I know for a fact that stock for stock our cars are faster, both because I've owned both and because most of the track results people have posted show the MS6 trapping 2-4mph faster than a 02-05 WRX. The 06 WRX is a slightly different story, they're a bit faster than previous models but we're still a bit faster than them as well. Not to mag/internet race but this article here shows we trap 4km/h (about 2mph) faster than an 06 as well
http://www.wheels.ca/features/jan_06_mazda6_vs_wrx.php and there are people running 13.7's in bone stock 06 WRX's
http://forums.nasioc.com/forums/showthread.php?t=979781 my only point in posting this is we're both AWD cars with similiar launching potential, only our cars are faster (evidenced by higher trap speeds, and I also test drove an 06 WRX Ltd that felt a good bit slower than our MS6s). With equal traction potential, and a better power to weight ratio 13.87 lb/hp to our 13.09 lb/hp (based on 06 WRX's 230hp & 3192 lbs curb weight & MS6's 274hp & 3589 lbs) I don't see any reason why our cars can't run a 13.6 or better bone stock. I think the only reason that no one has, or at least no one has posted it, is because the typical owners of the MS6 don't seem to have a track obsession like certain competitor cars (ie WRX's). That's just my $.02 though, I could be wrong.