I, like Jackie Spencer, have over 50 kits. I love kits! I make my own kits some times, but pre-made kits are delightful to me. My favorite place to order from is Fat Quarter Shop on line, fatquartershop.com . They give you ample fabric for your kits and I've NEVER had to call and ask for more due to mistakes. If the pattern calls for 6" of fabric, they give you a fat quarter! I have ALWAYS been extremely happy with their kits.
I just ordered from Fons and Porter and had to call them because my kit was short fabric, big time. But usually they give you just enough, and you hope you don't make mistakes. Connecting Threads has been good, also. I've boughten from everywhere and, like I said, Fat Quarter Shop puts everyplace else in the dust. And they have probably over 100 kits to choose from, ranging from wall hangings to king size quilts.