The wife and I both carry the Shield 9. GREAT carry gun, but make sure she's willing to learn to manipulate the slide. My wife has issues with the slide, and is "slack" about practicing with it. It's not ideal, but I keep the gun loaded for her, and she's slowly getting better with the tight spring. She DOES shoot the gun with incredible accuracy, but she needs more time "handling" it. Heck, buy one just to have one...it's actually my favorite gun to shoot at the range, even over my M&P9 full size.
Just my .02