All the loads I've seen put the 10mm well below the 41 magnum. I don't know about the plastique fantastique, but the S&W 1006 is a good steady platform w/nine rnd mag.

You'll need sumpthin' besides soft point and hollow point. I'm not sure if anyone makes a hard cast, heavy 10 round.

That being said the 357 has killed bears. Better than a spear or arrow, yet I wouldn't pick it out of the available calibers as a first choice.
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I only have to concern myself w/blk bear. I wouldn't take a .40 S&W if I thought I'd run into one of those. If she can't handle an adequate sized wheelgun then I'd be concerned about her ability to fire multiple rnds of upper limit 10's in a timely and accurate fashion.

Let me tell you what the 10mm ain't.

It ain't no one round grizzly bear stopper.

They make little 16" brl model 92 carbines that can be though...