Yes, they are great.
I have ordered 5 of their kits, the .58 Minie kit, .54 and .69 Minie, .69 roundball and have just ordered the .54 Round ball "Mississippi " kit.
The price is really fair and I use them as "starter kits" to get the forming dowel, to use the cartridge paper as a pattern and get the right size for the bundling paper. Then I use 3M Masking paper or 100% cotton printer paper (depending on the round) and make my own.
For $25 or so it's a great way to get started. In my opinion after you get the feel of one or two outings with the cartridges made with the kit , it's way cheaper to start with your own supplies.