I went to Silka for lunch a couple of weeks ago, and it was, to be honest, a little disappointing. A tad overpriced for what it was. The menu was v interesting, but not very well executed. The starters were good, but the mains were a little dry - bread was very dry, my lamb was overcooked and dry.
It's an interesting addition, but they will need to get the quality up a little. I wouldn't rush back, but may try again in 6-9 months.
We dined at ASK last night. Its next door to the Design Museum right on the Thames. Nice location.
If you haven't eaten there they have a large non-smoking area well away from the smokers. Its primarily a Pasta and Pizza place with most dishes under £10. Pleasant atmosphere. You may want to give it a try.