Product review (2 stars): Newer version of RWF1021 (to replace 4396701) is not how it used to be.
Purchased this product about 6 months ago for my Whirlpool (it normally used to take Whirlpool Pur filter #4396701), and had no problems with this generic replacement. When the indicator light recently went off, I did not hesitate to order another one. I did see the negative reviews about it breaking under the fridge and ruining people's floors and wondered about that... Upon receiving my newest one, I totally understand why. At first I couldn't get the filter to go in correctly and decided to put the two side by side.  They both said they were the same model (RWF1021), but they were not the same.  The newer one is longer and the way it screws in is not the same.  I took a picture and will try to attach it to this review -- The one on the right is the newer one.  You can see by the plastic tip it won't screw in the same and it is longer.  Also, the newer one looks like it could easily leak from the nozzle to where it attaches to the tube part.  It is not "sealed" -- or doesn't look fully sealed like my other one.  I am totally disgusted. What a waste.
3/18/16 UPDATE: DiscountFilterStore promptly contacted me and were concerned about my negative experience. They kindly refunded me the cost of the filter (extra star added for their good customer service) - Unfortunately, I do think people who are looking for a replacement filter for 4396701 need to know that the filter they receive may not be the best fit for their refrigerator. I am not sure what to think as the first one I received (back in October) was perfect, but this new one is not the same and won't fit right and looks like it could break and flood.