has anyone been? i've only seen this blog post which sounds great -
'Also noteworthy is that @Siam also does a special Thai menu – a good range of 5-8 dishes of no Western recognition – which changes almost daily. It is meant for Thai people who crave the home flavours, but the staff are more happy to cater anybody if the menu is called for. There might be a little translation hiccups along the way but you’ll get to experience Thai dishes you might not have heard of.'