I just helped a friend start the Cornucopia Pear Chardonnay this morning, be sure you mix it very well. The juice is highly concentrated, it's more like a syrup. The F-pack is about as big as the juice pack, so be sure you read the instructions and only make the primary to 21 liters.
It'll be interesting to see how these cheaper Amazon kits measure up to an Island Mist or equivalent. Time will tell.
Peace,
Bob