To be dead honest, with no intentions to offend anyone -
I'd have to say that the image quality between the various 35's is small.
Naturally, some will be sharper, have nicer bokeh or rendering (subjective), less distortion.
But with the bottleneck in the form of the scanner and for use on the web (i.e not printing big),
these differences will be minute and not that visible in real-life day to day usage.
What you should really consider is:
- size and usability
- do you really need a fast lens, which correlates to point #1.
- price
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Let me take your through my decision-making process.
I use the very affordable CV Color-Skopa 35 f/2.5 Pancake.
Size and usability:
One reason for me using an RF is size, I love that it's small.
So the size of the lens matters - the smaller and the more compact the better.
Being compact, it is also light and easier to bring around. I have my camera with me everyday at all times.
Of course, it is also less conspicuous.
Fast lens:
I like to shoot on the streets, I find that I hardly shoot wide-open - maybe just 20% of the time.
So considering that fast apertures are not a deal-breaker for me, f/2.5 is plenty for me.
Price:
Lastly, there's price. I am a full-time undergraduate and I fund myself by working during the weekends.
So price is a factor - the Color-Skopa being relatively slower, is much cheaper.
So I suggest an honest appraisal of your shooting style, habits, your penchant and your limits.
From there, you'd be able to find the lens that suits you the most.
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And lastly, there have been several 35mm lens test done here, all of which would prove informative.
Voigtländer Nokton 35mm f/1.2 II vs I on digital
Voigtländer Nokton 35mm f/1.2 II vs I on film
35mm Battle Royale - feat. Leica/ Zeiss/ Canon/ Konica/ Komura/ Voigtländer