Canon 24L 1.4 II or Sigma 35 mm?

I currently have  the Canon  24L II (and the 50L). I don't use it that much and I'm thinking of selling the 24 L to get the new Sigma 35 mm that is supposed to be second to none at f1.4.  It is a bit close in FL to my 50mm.

I love shallow DOF.

Would you sell the 24 L II to get the Sigma 35?

Will I gain IQ wide open by swopping?

Would love to hear your thoughts.

Thanks for any input.

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best regards
Michael
my portfolio:
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