FWIW, I've got Traxxas steel output yokes on stock sliders and they're holding up to 4S with a Medusa 36-60-2000. That's also with running buggy tires/wheels (Badlands knockoffs from eBay).
That's what I was running, but I added a spool and started snapping stub axles. Planetarys were lasting a few runs..........
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It's "Dr. _paralyzed_" actually. Not like with a PhD, but Doctor like in Dr. Pepper.