I think a few M1s were taken out with AT-14 hits to the engine compartment, which seems to be the most vulnerable area. Others were knocked out of action by DOZENS of RPG hits in massive ambushes. In every instance, the crew inside the tank survived, and made it out, even if the tank was trashed. This is world-class survivability.
I just hope we don't give up all the M1s in the name of "lighter, faster, and easier to kill with a cheap RPG". Let the MPs have Strykers so they can accompany "soft" supply convoys coming up from the rear. I want future bad guys to know that seeing our M1s means invulnerability for us, and certain death for them. We aren't over there to give them a "sporting chance" with a Stryker.