Quick thoughts on the J16 from someone who never had the OG version, courtesy of @kampongkid (pleasure to do business w/ btw).
I went down a size from XL to L, though the measurements are the same as the J28, the J16 feels true to size. I think if I sized down on the J28, it'd still be loose. The sound array took me a minute to figure out, headphone wire feeds through chest pocket unzipped & out through a tiny hole on the underside of the pocket. Though I do miss the mezzanine pockets on the 28, the 16 provides enough storage space all over the place. Overall really loving the jacket, not too loud nor dull.