The 642 is a great choice.

But don't expect to pick one up at the gun store and go out and shoot it like a marksman.

Small J frames are hard to shoot well. Harder than most semi autos. It takes lots of practice to master a 642.

The heavier all steel J frames like the M60, M640, and M649 are easier to shoot.

Easier, but still not easy.

If you have the money, perhaps get a 640 and learn it first and then move to the lighter 642.