Hey Arch. If you already have the 7s then go with it but if not, I recommend 10s or even 15s (what I use) but you can easily do 4 in a 4x4, any of those pot sizes. @overlord is doing 9 in 8s in a 4x4 right now. 4 tens is perfect for 1 kit and fit well. Let us know if you have any other questions.