I just could not face paying the price for a Sony external viewfinder, so I bought a Voigtlander from Amazon.co.uk for £128. I am thrilled with it. It is small, bright, and has lovely bright-line framing. It has no distortion for all practical purposes, and seems to accurately show the area actually captured. Together, the RX1 and the Voigtlander finder give me just what I want - the modern equivalent of the compact Rollei 35 I used to love. I would like to know why the RX1 f/2.0 lens can't be as small as the retractable Rollei f/2.8 lens, but the results are great.