Aspect seems to write metadata only to XMP sidecar files, please correct me if I am wrong.
I like having the ability to write metadata to the IPTC fields as well. Writing to XMP is fine for photos that stay on my computer and in my main collection, but not for photos I pass on to family members. They still want the information about who, what, where, when, but don’t have the technical knowledge to manage sidecar files. Most of them have no idea that sidecar files even exist, and probably don’t want to know. I know IPTC is an older standard, and more limited than XMP, but it still works on most photo software. It’s a kind of zero knowledge solution.
Cheers,
Gord