I have no idea what these people recommend, nor do I care. However, I'll share some 'off the beaten track' M1 recordings that I really like.
If it weren't for the annoying cut in the finale, the Paul Kletzki/Vienna Phil. one would be at the top of my list. The Wakasugi/Dresden Staatskapelle one is very satisfying. It has the right degree of rusticity to it. A 'sleeper' is the Eschenbach/RSO Berlin one, which also came with a very good set of Ruckert Lieder (I'm told that the Eschenbach/Houston one is also real good). Honeck/Pittsburgh is very powerful, but also rare and expensive. I really like the recent Adam Fischer/Dusseldorf one. It's similar to the M1 that his brother made in Budapest, but has more rusticity to it.
For one that reinserts "Blumine" into the second movement position, I really love the Jurowski/London Phil. one (I wish the LPO would release more Jurowski Mahler). On DVD, Bernstein/Vienna is very special, but I like Fabio Luisi/Dresden Staatskapelle even more.
For an sacd/cd hybrid, I'm pretty satisfied with J. Nott/Bamberg.