According to S&W, the incidents involving unintended lockup have been few and far between and most often happened when the revolver was firing hot loads. The incidents have become even more rare in the past few years. It would be interesting to see the total number of verified lockup compared to the total number of lock-equipped Smith & Wessons that have been sold.
The MIM myth, and if you ask anyone with a professional background in the subject, it is a myth, persists even as more manufacturers turn to the technology to produce more uniform parts at a lower unit cost. MIM parts are just as durable as those made by other methods in the proper application. Once again, it would be interesting to see the total number of MIM parts failures compared to the total number of MIM-part-containing firearms produced in teh past 20 years. It would also be interesting to see the failure rate of MIM parts compared to parts produced by other methods.
Perhaps someone has those numbers. If so, I'd like to see them. However, in Smtih & Wesson's case, it's my understanding that neither accidental lockups or MIM parts failures have been significant enough to cause a change in manufacturing or any defective-product legal actions. To me the incidence of either of these would have to be higher than the incidence of other common malfunctions to be considered a defect and nothing I have found so far indicates they are.
I have two modern Smith & Wesson J-frame revolvers, a Model 60-15 and a Model 637-2. Both have digested thousands of rounds of mixed ammo and have been dry-fired in practice even more thousands of times. They work every time. Neither of the internal locks have ever budged, even while firing Magnum or +P ammunition (in fairness, I seldom shoot more than 50-100 rounds of hot ammo per gun in one range session). There have been no problems with the parts. The triggers are very smooth and I don't find the pulls to be too heavy.
One other thing: Smith & Wesson has a lifetime warranty on new guns.
You should be careful of Smith & Wessons produced during the later 1970s and 1980s, toward the end of the Bangor Punta era. S&W's QC was apparently on vacation during much of that time and the couple of Smiths I bought in that time frame had issues, like timing being off badly enough to shave lead.
There has been political controversy surrounding Smith & Wesson in the past. I didn't agree with the boycott, though I didn't like the agreement S&W made with the Clinton Administration. S&W was up against almost certainly being sued into oblivion, setting the stage for similar actions with other gunmakers, and acted in its own best interests, which, to me, is how capitalism is supposed to work. By the time the lock actually appeared, both the White House and Smith & Wesson's new owner, Saf-T-Hammer, had repudiated the prior agreement but, since gun locks are Saf-T-Hammer's business, the locks remain and will likely be there a long time - like until there's a new owner.
I am not saying you should buy a new S&W or an old S&W. There are some very nice S&Ws no longer in production and you might be able to pick up a bargain. However, I have been very pleased with my two-year-old Smiths that were both bought brand-new.
You should buy what you feel best serves your needs, not what the prejudices of others recommend. You will never see me recommend a Glock or Kimber or Ruger LCP/LCR to anyone. Does that mean you shouldn't consider them? Yes, because I am the world's greatest expert on firearms and I know what's best for each individual. And I have some wonderful Florida property you'll want to invest in right away. You should make your own decision, but make it an informed decision.
