Well seeing as how none of us has given you a definite answer on the ATH T500.... I'm gonna say none of us have it. and googling it shows that this headphone is mainly..not in the US. So i'm sorry but i can't tell you that :/
however..there is already a thread on head fi
on it, a headphone supremus says
"these are very comfortable. the way-too-big headband suspension for the medium sized cups actually results in a very comfy setup. decent isolation. like a dj type headphone isolation but without the squeeze!
overnight burn-in- not much change. highs mellowed a little, but could be my perception only. spent some time with these today, sound is fairly neutral for an audio technica with a little aggressiveness in the mid highs and highs. still medium sized soundstage, did some gaming, worked well in l4d2.
needs an amp. played straight from an mp3 player these are bassless and harsh"
meaning these have good isolation...but would require an amp..., also it seems that the isolation is due to very high clamping force. which some users say hurts. The 440's i would say don't isolate as well, but they don't hurt...and the burn in period is probably shorter. in this case. the ATH T500's look like a better go than the Shure's for your case since they offer everything you want. Clamp it on a tissue box for a day or two and the clamping force should go down. however, this might lessen the isolation by a bit. and, just a "for your information" it looks like the magnets on these are form Grado :)
Overal I would say to get the ATH T500 with an FiiO E6 ($26 USD) and after some burn in and gettting used to. you will be one happy camper :)