In Quick Battles, the force selection screen is not resetting the quality options when you move back to attach single units, like in CMBN. For example, if you select a platoon to attach an individual unit, the quality options for the platoon leader carry over to the single unit screen instead of resetting to the settings used for selecting the battalion.
I selected an infantry battalion using typical for all the quality modifiers. I highlighted a platoon to attach a machine gun team, and when I selected the machine gun team instead of resetting the modifiers to typical, the machine gun team had the same quality as the platoon leader. So I have to reset the modifiers to typical each time I attach a unit. In CMBN the modifiers reset automatically so you don't have to do that if you want to make multiple attachments using typical quality.