For me, this is the new gold standard in collapsible ar stocks - FAB Defense GL-CORE S CQB Optimized Combat Stock

Prior to buying this FAB Defense GL-CORE S stock, my favorites were the Magpul STR and the MFT Minimalist (Mission First Tactical BattleLink Rifle Stock). The MFT is of course just about the lightest and most minimal but usable stock anyone would want with an AR. It also has an embedded Magpul QD ring which is located in the center of of the stock, vertically, for versatility. The Magpul STR of course has about the best check weld in the industry, and it has the option of mounting a Magpul QD ring on either side, but you have to pick the side to mount it. The FAB Defense GL-CORE S is smaller, lighter, and more compact than either the STR or MFT, and it's Magpul QD ring comes installed horizontally in a center location for easy use on the right or left of the stock. Finally, the FAB Defense GL-CORE S is cheaper than the STR and has a better cheek weld than the MFT. To be clear, any of these three stocks are excellent. But the FAB Defense GL-CORE S comes out on top in my book.