I suppose I'll have to confess that my favorite 1st symphony is Rachmaninoff's. It has received very few decent recordings. The best was Ormandy's first recording of it with the Philadelphia Orchestra, which I'd score at 94/100. It would be higher if it did not have cuts. Very fine on quality vinyl. Ashkenazy's recording is good -- 91/100. None of the other recordings comes close, and I've heard every one I could ever find. Most start out like some lead-footed dirge, which was definitely not what Rachmaninoff intended.
I know, I know. Gee, I wish I could say I love David Diamond's 1st better, or Paderewski, Suk, Scriabin, Tubin, Berlioz, Rangstrom, Chausson, Lyatoshinsky, Stanford, whatever. But I don't. Rachmaninoff's First tops my list, and Brahms' First is second on my list.