I visited Moscow twice within some weeks, once for private reasons and once for Business.
I had Arthur both as Guide and as Driver for several needed transports, mainly from and to Airport. I also booked some tours with him, one was the “Best of Moscow” and the other one, just recently was a “Moscow by Night” Tour. Arthur has a very deep knowledge about history and culture of Moscow/Russia, but he transfers his knowledge in an easy, sometimes also funny way.
He is very precise on time (very important for me as Swiss  ) and also knows how to avoid Moscow traffic jams, which saves a lot of time.
During my stays, my relation to Arthur turned from Client to Friend. I can highly recommend to book his services, it worth every Dollar, Euro or Ruble you invest in him.