LCT
ex-newbie
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I already have 3 Leica lenses (Summicron 35mm "King of Bokeh" 50mm Summicron Pre ASPH and a 90mm Elmarit pre-asph)
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Not sure if the M240 is made for you then as it is mediocre in LV/EVF mode and its strength are its rangefinder in the first place and its rendition with 16 to 28mm wides from Leica....
I like the rangefinder but honestly this is not something I cannot live without. That's why I like the idea that I could use the live view with the Leica M.
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Your Leica lenses are not wide enough to pose a problem to any modern sensor.
I would wait for the next FF Sony if you're not in a hurry or purchase an APS cam and a couple of wides from the same maker to avoid vignetting and color shift issues.