Honestly, from everything I have read on this and unfortunately that has been a lot. It is a problem with the lifter that is related to the MDS. Without the MDS these kinds of lifters would not be used. It was explained to me that when a lifter fails it can be a couple things. However, most of the time it is something along the lines where one of the lifters begins sticking and basically locks up, then it grinds the cam lobe flat. Again, I am not an expert, just going by what the shop who has does several of these is telling me. I don't think there is any rhyme or reasons as to which engines will have this issue, It is more a luck of the draw kind of thing. Sadly enough, for every person who is having symptoms like this Dodge should conducted an extensive examination on the engine with a scope and whatever is necessary to see why it is happening and make it right for the consumer.
Don't know if it is true but I have been told if you deactivate the MDS, it will void the warranty.