As the "Pancake" moniker suggests this lens is very small and sits almost flat on the camera. Invaluable as my quality WA option when hiking as the large wildlife lens takes up a lot of room in my bag and this tiny lens sits in my pocket. Build quality is as the 'Limited' name suggest, outstanding in every respect.
IQ is strong all around,though for the rather steep price it's not a stunning optical performer but it's all about portability. Excellent micro contrast and focuses surprisingly closely.