Gerald,
You left no wiggle room so I went with the first choice. I've used both MDF and Baltic birch ply as a substrate--MDF because it is a consistently flat product and birch ply because it is dense and has no voids. I have veneeered to solid wood as well and it can move quite a bit. While reconstituted sheetgoods are fairly recent, cabinetmakers have been making their own laminated pieces/parts for hundreds of years. Whether the unseen substrate for a panel is comprised of veneer or quartersawn strips does not weigh heavily on me. The real work is on the surface--the beauty of the panel is only skin deep. So to my mind, the real question is "Do we shun plywood because we did not make it ourselves? Because the laminations are not adhered to one another with hide glue? Because Russian birch was not a secondary wood used in the Colonies?" To follow this line of thinking, we should shun ready mix varnish and Dover inlays. And some do. The answer to this question speaks to the definition of the word reproduction and is it even possible today to make an 'exact reproduction' of any piece. Or do we all practice at reproducing to varying degrees? For me, this is one of the more interesting aspects of making historically-informed furniture in the 21st century.