This battery pack for my Panasonic Lumix not only costs a lot less than the original that failed me quite soon after I bought it, but it also works just fine with the original product.
The user who said that it was a waste of his money should just take advantage of the 2 year warranty and return it, since that is possible. I don't see though how his didn't work, since mine hasn't given me any trouble.
I've already used it on my original camera and so far it hasn't shown any signs of being inefficient. Actually, surprisingly, it has worked better than the one I had with the camera. I say surprisingly because I wasn't expecting a replacement to work better than it, especially since the price is considerably lower than that of a Panasonic camera battery.
I'm very happy with it and would recommend it to those looking for a replacement for the Panasonic cameras compatible with it.