Hi Joe,
The Moss (include TRF and VB in this comment) seats happen to be very good. Moss does not make them themselves, but I have used theirs and the Victoria British offerings before and find their sources seem to have the fit and finish down well. The older foam cushions seem to work better with any of these as well (hence the use of '72 patterns on my seats). While not an issue with your seats, I found adding some memory foam into the recess of the sculpted foam seat base works better with my upholstery on later foams.
I do not have real experience with installing or living with the Prestige product, though I have heard several that have tried them say they do like them. They are rated better than Autocraft and other mass-market makers, but the fit is not as exact as the restoration catalogs offer and may require some additional foam and/or adjustments to really look right. Not so bad, and often more comfortable as a result, but not quite original. They did offer a good idea in a leather fascia seat (leather seating surfaces only with matching vinyl sides and backs) that helped as an alternative to the ever increasing cost of the Moss and VB offerings and they looked uniform, but they are not exactly original.
Also, if going the leather route, the replacements by all are "representative" and may not be the exact construction or pleat width, so, while no one but the most stringent judge would see (or care about) the difference, they may not be entirely as original.
I hope that helps you.
Art