I tried the sulfite. The print made me want to clean my glasses where they weren't dirty. I tried this once several years ago with Rodinal and the results were published in Photo Techniques. I didn't like it then. I thought 4 grams of sodium ascorbate in a liter of 1+50 Rodinal were better than 100 grams of sulfite. Salt helps a bit in rather massive amounts. It takes about 100 grams of canning salt or non-iodized table salt per liter of working solution. I have not used it since because I didn't think it was worth the trouble, and it isn't really much trouble.
My test just a while ago was with HP5+ which is fundamentally low in contrast. I found once upon a time that the highest CI i could get in Rodinal was about 0.65. Metolal seems to be even more resistent to high contrast with HP5+, though it certainly keeps detail the shadows even at less than normal contrast.
But don't take my word. Play with it yourself.