Oh, right. So my comments before would mostly apply to the old packaging. Old packaging 50-pack TDK was mostly CMC (MIT), with some Prodisc (MIT) and Daxon (MIM) spinkled here and there, but now it appears they've switched to mostly Ritek (MIT).
Just as an FYI, although this sale is about the 50-pack, I do think you can still find some Daxon (MIM) in the 100-pack. I haven't seen any at Office Depot, but I have found lots of it at OfficeMax.