It's one heck of a lens, though not so keen on that review...can't really stand the sound of the reviewer. It is a rather large lens when mounted onto an M body. Looks like the size of an SLR 50 1.4 bolted onto an M body...rather large when compared to the Summilux or Summicron.
What would have been much impressive to see is taking photos in a dimmer environment. Hong Kong isn't the darkest city in the world at night, especially with the amount of lamps around. Yes, I've tested this myself with a Summicron 50mm