I go to Pert Holborn (on Theobald's Road, next to the Subway and the Butcher) one or twice a week (Careful, there are about 10 Pret in the area around Holborn). They are a trial site for new sandwiches and salads. Don't be afrain of queues, the team is efficient and usually you get to the counter within 1-2 min and you get your coffee very quickly.
The seats are limited!.
The new Pret next to Russell Square Tube station has the same good service and lots more seats)
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