If I were to get another J Frame to replace my 638 with, it would be a 340 M&P. I consider the 340 M&P to be an improvement over the 638, mainly because of the sights.
I have a 340 M&P. It's a nice gun if you intend to use .357 mag ( most won't). And the big dot is nice, but it's hard to justify when you can get two 642 no-locks for the same price.
I've often thought of selling mine and just using my 642. But all my J frames just fill a back-up roll to my G23.
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