I will come to Russia next year because ı want to learn Russian so ı want to know which city better for live ? :)
I've been there five years ago.I think It is best to visit Moscow because first of all it is cheaper than St. Petersburg also St. Petersburgs slightly is more colder than Moscow due to it's location in the Arctic Circle. And to me Moscow is more Russian than St. Petersburg... St. Petersburg is more European than Russian. Also Moscow is culturally active.
Russian go to Moskow for earn money. St. Petersburg is a Capital of culture in Russia. Climate is better in Moscow. But to live is more cheap in Peterburg