I hear you.... I have 4 of these IP5000 50C LIPOS, and all of them are puffed slightly, with one of them so bad that its split the casing. Not very happy as they are only about 3 months old.
A couple of other racers at my local club have them, and they are starting to puff too, with one pack of MOK's going open circuit.
I'm gonna stay away from these packs, and probably this brand in particular....