I have a S&W model 49 and 642 and love them both. I bought the 642 for my wfe, but found the trigger pull too much for her. I thought of having the trigger worked, but decided to keep it for myself and I bought her a S&W M&P 9 Compact. I thought the revolver would be simpler for her to use, but she really likes the compact.
As for the lock, and I don't want to start a war as I've seen on other forums, but mine has never been locked and has never had any problems. I don't use the passenger visor mirror in my vehicle, but it's never caused me any problems so it doesn't bother me that it's there

. I guess if it bothers others they can just buy something else.
If possible, I would suggest let your wife shoot different models to see which she likes best. Good luck!