Don't take this too literally, you serious-minded gentlemen. 

I went into the Regent Street store a day or so after it opened and thought it rather ho-hum.  But I showed willing and bought a shirt.  A ho-hum shirt as it turned out.  I didn't bother again until I wanted a white shirt for a wedding so chanced it for the second - and last - time (for which I received a mild rebuke from Gibson Gardens).  The salesman was a tosser and some of the sweaters I turned over expensive Chinese-made cashmere - putting me very much in mind of stuff I'd seen in M&S whilst looking for something or other.  Christ, if I saw a decent overcoat now made by M&S in England (which might be going back a while, admittedly) I'd probably consider it over anything doing the rounds now (not NOS or whatever, contemporary). 
I never went back.  I took GGs advice.