This is a precious item indeed, but it's not for beginners or anyone who must have good quality sound. The 4-star rating is the best I can do to indicate that this is a record of a unique duo with a very special pedigree in the interpretation of Beethoven. It sounds to me as if they are at their formidable best. The rhythmic command is such as nothing can disguise, quite a lot comes through of the marvellous phrasing, the players' technical magnificence is is obvious, and the whole disc just exudes authority. If you know these players, your imagination will fill in much of the deficiency of the recording. There is no point in trying to compare a historic reissue like this with any modern versions, but as I have the Kreuzer done by Kulenkampff and Solti (yes, that Solti) I spun their version just to get some focus on Busch and Serkin. K and S are top-class, it almost goes without saying, and the general approach taken by both duos is not all that different. However I could not help sighing when the recorded sound of Busch and Serkin had the greatest difficulty in coping with them -- when Serkin leads off the great striding theme in the first movement. My imagination was having to compensate in a big way, but I bet that must have been a real experience to hear live, something extra-special.
In keeping with the ideas of the time, the violin is in the foreground, and the piano is treated as 'accompaniment' in spite of these sonatas being described as for piano and violin, not the other way about. Our technology has come a long way, our musical culture and understanding of the composer has advanced, not least as a result of the efforts of Busch and his modest son-in-law, but some artists can never be replaced. Be thankful to get anything you can of them.