The nature of the local supermarkets themselves dictates my choice, or lack of choice.
At Asda, the biggest supermarket in town, there are usually only two or three checkouts in operation, and sometimes none at all at quieter periods. This makes the self-checkout the usual logical choice, and to be honest, it's fine - the machines are pretty reliable and I can get my shopping processed within a minute or two.
At Aldi, where I shop fairly often because of the prices, there's only the cashier option. This also is pretty good - Aldi is known for encouraging its checkout staff to get stuff scanned with a minimum of delays, and they'll also open up other tills if there are too many people in the queue.
One thing that's always annoyed me about the supermarket cashier system is the way they always have to send for a manager if there's a problem with the transaction or with a product. It sometimes takes several minutes for the manager to arrive, and all he or she then does is to stick a key into the till and make some minor adjustment. Why on earth can't the cashiers be trained or trusted to do this themselves? It would get rid of quite a few hold ups.
Another thing that used to be a problem with cashiers at some supermarkets was their tendency to chat with customers, slowing down the scanning process and leaving several people in the queue (like me) fuming with exasperation. This doesn't seem to happen much these days though, and never has at Aldi, as previously mentioned.
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On a mountain range
I'm Doctor Strange