They weight an extra ton over a normal cockpit, you get a +1 to all Piloting Skill rolls, and you can't eject. While you don't take pilot hits from shots hitting the CT like you do when you get hit in the head, its worth noting that due to the way damage transfers, as the fighting goes on, more and more shots are going to be heading for the CT. And with no ejection...
Admittedly, that might be more of a campaign issue rather than a simple fight, it is worth mentioning.
Also, while you'll survive the head being destroyed, its likely that your 'Mech will be so screwed up from the loss of sensors that your opponent may as well have just destroyed the 'Mech anyway.
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And forgot something. With the life support moved to the side torsos, you're likely to lose one at some point, and if you do, you start taking damage for ANY heat above 0 in the heat phase.
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