He was definitely an interesting composer, and a very long lived one (died at around 108 years of age). His early works are in a very harsh, jarring idiom, but are very enjoyable and passionate works. His later, more neoromantic works are a mixed bag to me. Some works are very good, and others are not so much. His piano sonatas, which are in this later idiom, are worth exploring. Take a look at Hamelin's disk for a nice anthology of his works. He also has a very good piano quintet worth looking at.