I've used and still use the cranberry extract, but I also have experience with the Piece Water. The cranberry extract is really good for keeping your piece clean, but I would always change it out after 2-3 days. Always afraid of getting some "growth" in the water since you're dealing with something organic. It does work great though!
The Piece Water really works well for getting a lot of days out of your glass. I've kept it going occasionally for up to 3 weeks. When it's time to change it out, just rinse out with some hot water. I do ISO it also, and then rinse again. Comes out perfect.
The few negatives (to me) are: Only stays clear for a day or 3 before starting to cloud up. Not a biggie, but it bugs me a bit. Then there's the smell.
Oh, it has no smell when it's clean and fresh, but by the second week it has a particular rank from all that vapor passing through it, that I find a bit unappealing.
As to the price. If you use it moderately and not vaping all day long, one filling will last at least a couple of weeks. So if you buy the 3 pack, it can last you a number of months.
Like I said, I use it along with switching to the cranberry extract as the mood strikes me. I usually buy the Piece Water once or twice a year and always with a holiday discount like when this next 4/20 arrives. They always have a good deal for days like that.
