User blog comment:Hamtdog/Question/@comment-4988993-20120502000122

Hi Hamtdog, there are actually a few reasons that you should upgrade after lvl 6. Number one is for looks, showing that you have extra money and resources to upgrade your village. Second is for the good amount of XP that it gives after building. The MAJOR reason why the magic rock should be upgraded is for the Wonders of the World Challenge, that REQUIRES that the magic rock is lvl 7 and lvl 8 to get those decorations. One of these decorations give one crystal a day, and the challenges give crystals and big money as well. So it is worth it if you have the extra money to start saving for those decorations.