I dunno if it's that great as to include in default, it makes the inventory screen look uglier. Besides, in vanilla it's only 4 TUs to 'quickdraw' a pistol/knife from a belt slot. Sure it's not instawin like in this mod because it's realistic - it takes more than crazy zero time, but it saved my soldier's ass more than once still.
I like the mod, but not enough to condone putting it in the basic build, even as an option.