Quite a recommendation for the String Quartets II and IV!
Many thanks for the comments!
Yes, the Piano Trio is an all-around fave, and chamber music is normally not my thing. But Taneyev convinces me that at least his chamber music should be my thing! The CD with this from Pro Arte also offers the Alexander Tcherepnin Trio.
This Odeon Trio recording is my favorite recording so far of the Taneyev (I have it on Lp). I also have the Pletnev et al. on DG and the Northern Flowers. I don't like the piano playing on the Northern Flowers. I'd like to have the Odeon on CD, but rather than spend $25 to get the CD, I wonder if I should try one of the other available recordings, which as far as I can find out are:
Borodin Trio (Chandos, and Brilliant Classics, I think)
Mendelssohn Piano Trio (Centaur)
Barbican Piano Trio (Dutton)
Röhn (?) Piano Tro (Calig)
Moscow Piano Trio (Chant du Monde)
Roslavets Trio (Vista Vera)