Depends on what you're ordering and who the cashier is.
If your order is the happy path of no customizations of a combo with an experienced cashier, it can be done in seconds, for sure. "Medium #4 with a Diet Coke", pay, done.
But if you customize your burger or ordering a lot of items a la carte and you're dealing with a new cashier that has weak English skills, good fucking luck. You'll likely need to wait for them to figure out they need to call someone over to help, have to repeat your order, and you end up spending far more time.
> it keeps trying to upsell you
Yeah, I'll agree that's obnoxious, especially when it's trying to upsell you something that's already on your order. I ordered a combo. I don't need you to add another fry.
I have had them run out of receipts, but it’s never mattered for me. If I’m dining in, the plastic number you carry to your table makes sure I get my food. And if I’m taking it to-go, they always find me anyways.
I'm not sure how that could be. I can walk up to the counter and say "Big Mac Large Fry Small Coke" faster than you can navigate the first screen of the kiosk, and a skilled counter worker can key that in and be done before I even get my credit card out.