Product review (1 stars): I recommend the HDX FMS-1 to anyone who reads my review
Keep shopping.  You have to trim the leading edge of the serrations on the locking mechanism to make it work (THANKS to Gary Edward's review).  You should not have to do this.  I'm lucky I didn't break my fridge.  The HDX FMS-1 that I used previously works perfectly.  I bought the Samsung AquaPure Plus because I thought it was a "factory" filter, but apparently not.  I recommend the HDX FMS-1 to anyone who reads my review.