I've tried to run with clockwork 3.x twice now, and both times my SD card (ext partition) got screwed up to the point that it couldn't mount. The only way I could recover was to reformat the entire card.
I don't know if it was clockwork 3.x, or user error, or just coincidence, but I've never had this problem at other times...
The web is full of similar examples, so until I know for sure, I refuse to use 3.x (I'm a clockwork fan, and use 188.8.131.52).
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