That's been in the UK for ages. Like 5 years. Everything works fine, have been to a McD's dozens of times over the last few years and never seen a problem, apart from sometimes the printer is low ink.
The reason it takes longer has nothing to do with the touch screens. It's because the stores that are touch screen are now cooking to order, no picking stuff cooked already off warming shelves.
It is annoying when you want to grab something quick. But on the other hand, no more floppy, soggy, burgers. Everything is freshly cooked. Less waste.
They just have coupled the two changes, touch screens + cook to order, together. So when a store gets one, they get the other. And if you look behind the serving counter you should be able to see the difference, no warming shelves, but a slide that fresh food is coming down, which gets immediately bagged and then put straight into your hand.