I used them in Tesco many times it's was horrible expirience too. Sometime they didn't work properly or failed to scan something. What worse shortly after some

I used them in Tesco many times it's was horrible expirience too. Sometime they didn't work properly or failed to scan something. What worse shortly after some stores in London got those there was less cashiers working at eventide. So you had to choose between unpleasant expirience or long queue.