The Mini-14 is reliable, but not durable. It's a fine commercial/sporting arm, best when use is kept light. Lube generously. Inspect often.
The biggest difference between the SS and blue models will be in corrosion resistance of the metals. The effect of barrel heating on POI is less apparent with the SS than the blue.
There are a number of small tweaks that can be made to improve accuracy on the Mini.
The newest rendition of the Mini (580) is better than the previous in most regards. I recommend the SS over the blue. Getting the 16" barreled model is also recommended.
A substantial shortcoming of the Mini in your case will be accomplishing best fit for your wife. The stock is a traditional commercial LOP, generally regarded as too long for even adult males.
If limited to those two options (BM or Mini-14), I would keep the BM.
2012 National Zumba Endurance Champion
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