So, in this situation (see details) would I be guilty of "mixing batteries," and if so, what price will I pay for my sin?

I have always heard that you shouldn’t “mix batteries.” I want to use my label maker tonight and the batteries in it are dead and I can’t find the A.C. cord. So… if I want to use it tonight, I have to go with batteries I have. The label maker takes 8 AA batteries.

I have 6 fresh Duracells and 4 fresh Energizers, all standard alkaline, AA batteries. The Duracells and Energizers also all happen to have the same expiration date, March 2017.

If I want to use the label maker tonight, and I’m not going out to get more batteries at this point, there is going to have to be some “mixing,” if only by manufacturer. Normally I wouldn’t do it, but what, really, am I risking if I were to “mix batteries”?

I have Googled this already and there seem to be mixed opinions on this.