I have not had any of my cells vent yet and the only explosion I know of was a four cell pack at IIC. That only happened because the pack somehow got pushed into Integy charger with a metal case which dead shorted the whole pack to point of explosion. I have seen other cells vent but again because of something causing a dead short issue such as a screw touching the end of the cell or cells shorting out with too much solder coming off the battery connector. I personally had the last one happen to me and the four cell explosion in LV was a friend of mine. That was just something bizarre. We think someone used his pit while he was away and just pushed the pack out of the way and pushed it right into his charger. I saw the screw thing just last weekend in a new Gen X 12. So everything I have seen go bad with these cells has more or less been human error.
JRXS Type R, I have four of them!! ;) ( Yes, I still have them!!)