Then it might be a matter of preferance or ability, because I can play lots  tunes on the B3.  However, I have ordered a Moog, and will report on my experience, and what I find to be the differance between the two.
Only thing is, I hate to spend that sort of money, only to have to play the instrument  "backwards."  That is, with the controls facing away from me; being left handed.  I wrote a guy at Moog, and complained about how a short run of lefthanded theremins would not cost them that much!  Hie sort of apologized, and told me how to rewire the thing, which is beyond my skill or desire.