Yes, but... the sound on those old Columbia recordings isn't what RCA gave Zinman - and if ever there was a composer where sound quality matters, it's Mahler! No Mahler collection should be without Bernstein in both the Sony and DG (better sound) versions. Skip his DVDs - too many errors and lousy sound. When it comes down to it, Bernstein was likely the greatest Mahler interpreter of them all. He possessed the maniacal drive of Solti, the gemutlichkeit of Walter, the architectural sense of Tennstedt, and the pacing that makes Bertini so enjoyable - he doesn't get bogged down like Klemperer, Maazel, and several others. His NYPO was good, great at times, but his DG remakes had better orchestras by far.
I wouldn't be so quick to write off the Sony stuff. The old Columbia LPs were awful (I have a complete set) but the remastering for the Bernstein box is quite impressive. The recordings may not be quite up to the best of Decca, Mercury or RCA Living Stereo, but they also don't have that super multi-miked wall to wall of processed sound that many (not all) DG recordings had from the late 60s on. Moreover, the newer reissues do give you more of a sense of space and a natural hall that is typical of well engineered recordings from the 1960s. Again, while I enjoy many of the more unnatural sounding Karajan Berlin recordings and I do love some of the Bernstein DG set (I have both his Mahler sets) as a general rule, there is enough that's objectionable in that late set (speaking purely in engineering terms) to make the Sony Mahler viable. Listening to DG recordings I sometimes have this image of German engineers forcing every piece into a particular mold and endlessly twiddling dials. It's probably unfair but it reminds me of a debate I heard at a conference where representatives of the German and Belgian brewing industries were arguing about beer. The Germans were claiming that their regulations delimited what constituted "beer" and therefore guaranteed quality, while the Belgians wanted to encourage experimentation and more varied approaches to brewing.