Use the Core version that shares the kernel version being dealt with. By being built on Core, each dCore that uses 3.16.6-tinycore can share kernel module packages. If each dCore version was used to build it's own kernel, that means there would be no sharing of kernel module packages across them though they used the same kernel, say 3.16.6-tinycore. As the kernel modules need to be built with the same version of GCC as the main kernel image. This way is much more efficient.