Peter Cropper was exactly right about the 1st violin vibrato in the slow movement. I have simply never heard that movement played like that, and I feel rather ashamed to have reached my age and never heard this Busch Qt version. The intensity, yet simplicity of the reading, the sheer length of line is astounding, as Adolf Busch just keeps on relentlessly ( in the very best sense of that word) improvising, thinking out new lines and ideas as if the quartet were being composed there and then. And the result is that the finale feels like a totally new world, as if we had arrived somewhere else altogether from where we set out. Unforgettable late night experience.