I've had a few with the lock. Never had a problem with it, other than hating the hole in the side, until I bought an Airweight 642. I have had S&Ws with the lock in 357, a pair of them, 340PD and 386, and never had them lock up when firing. I had read of people having that problem, and S&W, and others denying the validity.
Well .... I bought the Airweight, immediately went into the indoor range at the LGS where I made the purchase, and within one cylinder the gun was locked up tighter than a drum. This was a lightly used piece.
I went out to the counter and the clerk took a S&W key and fiddled with the lock. Got the Airweight functioning again. I went back to the range and on the second cylinder fired it was locked up again.
I went back out to the counter ....... "It's not the lock," said the guy, 'must be something else,' if you want I'll take the sideplate off and have a look. I said do it.
When it was off, and there was nothing apparently wrong with the internals, I said do me a favor, take that damned lock out of there, and I'll never tell a soul you did. (I had my fingers crossed)
So he took the lock out and the revolver has functioned flawlessly for many rounds since. If I really want a particular model S&W, and it is only available with the lock, I will buy one, but as soon as I get it that lock is coming out.
I am 68, no kids, grandkids, and live alone. I won't worry about any legal ramifications if I get in a shooting scrape due to removing the infernal internal lock. That is my story, and I'm sticking to it.