Although blitzkrieg-ishly fast and agile, they had a very limited range and from what I know, they were death traps. A lot of them blew on landing due to the unorthodox lack of wheels.
Didn't they canceled it or something like that because of the obvious reasons?
The fuel was a binary explosive - two tanks of chemicals which, when mixed, spontaneously exploded (no seperate ignition needed). As you can imagine, if you crashed, and the tanks ruptured, and mixed.... I read a book about the luftwaffe's experimental aircraft a few years ago and there was a first-hand account from a mechanic who'd gone over to help a 163 that had crash-landed and caught fire, and he found the pilot sitting some distance away with no skin left on his face.
They were designed to incercept bombers at extremely short notice (conventional interceptors took half an hour or so to reach the height of the bombers and engage, so couldn't respond quickly) so they'd take off and have just enough fuel for a near vertical climb to 30,000 feet, and one pass at the targets before they'd run out and have to return.