My Sam's switched to that for basically all their beef a little over a year ago. A little improvement for a lot of cuts, but not a huge difference. Biggest thing I ahve noticed is that the briskets are now always USDA Choice, every one of them.
IMHO, it was just to make the product more attractive. Maybe some consistency was desired too. I think it was overall a positive switch, but not a major improvement either, if that makes sense.