I used a MLS Colossus arms and legs on MLS Thor body. He looks okay. The big concern with Cable customs is size and doing one flesh arm and one bionic arm.
You can kind of argue the "Why make one when an official one is assuredly coming" is true for nearly every active line.
I can see if one had been announced and you weren't happy with it so you decided to go ahead with your own. But Cable has been confirmed and it's arguably iffy if he'd come out anytime in the next year.
I say go for it!
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