I think they're different from what I've read. The Crystal Nylons are the old ones that have been on market for a while and generally have mixed reviews. The Modified True is the newer version that Martin announced over the summer, so the people at the Martin forum say. I've only read 1 review for the new one and it was favorable. I've been meaning to try some of the Modified True Sopranos when I can find them in my local stores, they only carry the Crystals atm. Hope this helps!