Oh, how you put me on the spot!
It's wonderful — very personal, unique music that is "romantic" without sounding like a throwback or like film music. The first symphony is an early work but is very assured in its orchestration and melodic writing. I can see why Schoenberg called him "the new Bruckner", because his slow movements are certainly of a rare beauty. The violin concerto is also lovely, with a very memorable theme providing the basis of the first movement and a rollicking final rondo. The gem of the disc, for me, is the tone poem The Enormous Room, which eventually builds up from quiet beginnings to a climax that is (really) breathtaking.
I'll be going through Naxos traversal of the symphonies (alas, woefully incomplete) over the next several days and will post my thoughts here.