From my bit of research:
https://www.snipershide.com/shooting/threads/desert-tech-mdr-opinions.6921855/
https://www.snipershide.com/shooting/threads/mdr-update.6928764/
It seems they at least tried to fix the issues in 2019. I look on their site now and see they have a "Side Eject" version...
I found this forum while looking for a Desert Tech MDRX. I saw that you guys are a pretty active forum. Would be cool to learn a bit and maybe teach a bit if I can. I am in Washington and am currently looking for an MDRX in 6.5 Creed or 7.62/.308 (20 inch barrel) hit me up if you know anyone...
For sale is a used MDR conversion kit in 5.56 (.223 Wylde), 16" length. Confirmed compatible with MDRX Chassis (as well of course the MDR) per Desert Tech. Save yourself $200 + taxes and shipping off a new conversion kit - looking for $450 shipped to you!
Kit comes with everything in the photos.