The Profile you were using at the time your 360 was banned will be corrupted, along with your saves at that point and after, even if you were using your memory unit, they will show up as corrupted on other 360 consoles.
So even if you took your MU to a friends house and played it on his banned console your Profile and saves on the MU will be corrupted with no way of getting them back on your legit console without Live/Internet access. M$ do indeed suck, has to be a lawsuit right there, they could say 'but its your friends fault and he should have warned you', but YOU would have done nothing wrong, and nothing would have displayed on the screen to warn you that your profile would be corrupted if played on your friends xbox, this kind of crap along with all the rest of the crap M$ is doing is effecting their sales far more than they know, its amazing how out of touch these large companies can be. M$ should have had the market wrapped up by now, bunch of fools.
As for you HDD it may also get corrupted if you do decide to hook it back up to the banned 360, I have not personally tried the latter, only going by what others have said, if its a big HDD like 60-120gb then save it for use with another none banned 360, good luck avoiding the bans.
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