I have entered that boutique once and I can confirm that the service is rubbish there. In fact, I have been quite let down by the Rolex boutiques in London be it at their flagship Knightsbridge branch, Heathrow Airport, Harrods and Selfridges. The Brand was always popular but as demand exceeds supply for at least half a dozen models including the watch you were mentioning, there seems to be an arrogant attitude adopted by many sales people. It is almost like they would be doing you a favour to add you to the waiting list.