Most people who have not worked with the high velocity 17s would think they are not well suited to defense. Having shot them a great deal into clothing draped ballistic gel I can say the little bullet will make a fearful wound that will discourage most folks pretty quickly. Now, I would not say that the 17 is the best choice for self defense. I would say that for the recoil shy it is an option better than a 22. The wound it will make is very large and very devastating. Will it crush bone? No, but neither will any other load that is very ight recoil. I will also state that I have watched a man shot in the butt with a 1 oz. 12 ga slug out run 3 yound officers.
As far a Taurus revolvers go. They are probably just like Colt or Smiths or any other. Good ones and bad ones. I can tell you that the ones I have shot are quite good. I have a Model 85 2" 38 Spl. that has over 2000 rounds through it and it has never had any problems. I could also tell you of the new Smith I just sent back which would not rotate the cylinder out of the box. This does not mean I think all Smith's are bad, just this one.
I know Michael Bane also shoots some Taurus revolvers with no problems.
I just passed the 1,000,000 round mark from revolvers in '06 so I have a fair understanding of their use and potential. If weight and transportation were not an issue and the lady could handle recoil, I would suggest a cartridge starting with a .4 . If defense is from 4 legged animals such as bear, I would suggest a cartridge starting with .4 . But, for a woman unfamiliar with shooting, who will not shoot much, who is looking to discourage two legged animals, I would suggest the most shootable firearm chambered in the most shootable cartridge so that she is most likely to obtain a hit After seeing the results of shooting the 17 Mach2 into gel, I will stick to that recommendation.
Mike