I used to have an old Century Tidal Wave heavy bag that I got in the early-90's. I always liked the feel of it. The water core was in a rubber bladder surrounded by heavy foam, and that gave the bag a hard enough yet fluid feeling. A lot easier on the joints. I had to store that bag for a few years, and recently got a new space for it. I tried to hang it, but the glue holding the bladder's filler got dried out, and it just came out on my hand. I contacted Century, sent them the cover of my old bag, and they sent me a whole new Hydrocore bag since they don't make the Tidal Wave anymore. Big props to Century for the replacement, but I hate this new bag. The old rubber bladder has been replaced with a hard plastic bottle. Granted it makes it easier to fill it. Yet it is just too hard. It is a very hard plastic bottle surrounded by about 2 inches of hard foam. It feels like punching a building's columns. Does anyone still make water-filled heavy bags with soft cores rather than hard plastic bottles?