There are three kinds of 10mm mags: 1st model has yellow follower and a beveled front. 2nd model has a white follower. Third is also a white follower with "accu-glide" written on the side. There is no difference in performance, only that the yellow ones are older.
All my yellow ones have stronger Wolff replacement springs and they actually perform better than the newest accu-glides. Its great having them color coded for me.