I have a M&P Shield .40 cal. I have looked at a lot of video's on SD ammo reviews and they pretty much all look good. I have 3 types of SD ammo I can choose to use. i got Hornady Critical defense 165 grn. I have Federal Hydrashocks 165 grn, and Winchester Whitebox JHP 180 grn. I know the WWB JHP are basically Winchester Ranger but with brass case. Out of what I have, and if anyone is experienced with this, which SD rounds should I use for my Shield? Guy at the gun store told me all american SD rounds are plus to minus 5% effective and I can't go wrong with just choosing one. Thanks guys, sorry if this is a topic that might have been discussed before, new to guns, new to CC and new to ammo selection.