DxOMark are doing their measurements on unprocessed RAW files. They identified the best model in different categories.
According to DxOMark the SONY NEX Top Primes include Sony 50mm f/1.8, Sony Carl Zeiss Sonnar T* E 24mm F1.8 ZA, Sony SEL35F18 35mm f/1.8. Interesting enough the best prime DxOMark selected is the Sony 50mm f/1.8 costs less then 300 USD and the second best (Sony Carl Zeiss Sonnar T* E 24mm F1.8 ZA) is below 1000 USD. When it comes to Zoom Lenses my favorite one the Sony SEL1018 10-18mm scores highest.
One think to keep in mind is that while the SONY lenses score low compared to Canon L lenses we use. However the quality of the photos that you can get from a Canon L lense compared to the SONY lenses do not provide a different image, at least for me.