This concerto manages to accomplish what many cannot; it is both challenging and virtuostic while still maintaining a lovely lyrical quality throughout. It is romanticism/impressionism at its best, and, in my opinion, should be played much more than it is.
The difficulty level is high; I have played for over eleven years and still find this challenging but definitely do-able. It is comparable to the Bruch violin concerto and possibly not quite as challenging as the Mendhelsson.
I recommend getting Joshua Bell or Itzchak Perlman's recordings of this; both do an excellent job.