I like the brunch food menu for its variety - you can have anything from a fry up (in various permutations) to a BLT to a proper main course like sausage and mash. (Sensibly though, unlike the near-by 24-hour caff Tinseltown, they don't offer Thai green curry - hang offer food that ain't, as my husband once discovered the hard way.) On the last two visits I've had the eggs benedict with smoked salmon (£8.50), served on a halved muffin and smeared in creamy hollandaise. Their macaroni cheese with haddock (£6.50) isn't bad, but not cheesy enough. The club sandwich is huge, and the BLTs (£6.50) are also pretty good. Just don't try to economise with something like egg on toast (£2.50) - you will feel very jealous when everyone else gets their food.
Other than always being very busy, the other (no doubt related) drawback is the service, which can be a bit slow and a bit inattentive, especially if you order extra drinks). But for me the food and the buzzing atmosphere tip the balance firmly in SOS's favour. Plus Santa(s) and his(their) reindeer brunch there. (Oh, ok, it was probably just real people we saw lining their stomachs ahead of Santacon, but it was still cool.)
Smiths of Smithfield, 67-77 Charterhouse Street, EC1M 6HJ; Tel. 0207 251 7950; Tube: Barbican or Farringdon; www.smithsofsmithfield.co.uk