Should you ever be seeking an alternative to the Ladurée macarons I can highly recommend Pierre Hermes located in Knightsbridge. Quality is definitely up there but their uniqueness comes in their adventurousness with their flavourings. I walked into the shop just to have a look but walked out with a whole box! Interestingly on this occasion they charged by the weight rather than piece.

Flavours, left to right,

Mogador – Milk Chocolate & Passion Fruit
Chocolate
Olive Oil and Vanilla
Rose and Rose Petals
Pistachio
Ifiniment Caramel – Salted-Butter Caramel
Crème Brulee – Vanilla & Caramel Bits

They also have a concession in Selfridges if Kinghtsbridge is out of the way.