Why did I buy it? Well, it' s a 357 that can handle loads meaner than a prudent man wants to hold
Sorry, no, not that gun, unless your "prudent man" is rather wimpy...
A buddy of mine had one (4") back in the day. I was using my father's 6" S&W Highway Patrolman. The bigger heavier N frame S&W handled hotter reloads, and recoiled less.
The Security Six is a stout gun, but it is still a medium frame gun. Tougher than a model 19, I think, but NOT able to handle what a .357 N frame S&W can. You got a hell for stout snubbie .357, but its still a snubbie...
The bigger Ruger REDHAWKs would be even stronger.
And, remember, we're not talking about blow up strength. (if you aren't blowing up the gun, then blowup strength doesn't MATTER.) What we're taking about here is working "strength", meaning what level of loads not only fire safely but also extract easily.
I'd CALL Ruger, and see what services they still offer for that model gun, and the costs, including shipping. Once you know that, you can make a better informed decision.
Nice gun, with a bit of surface issues. Good price. You could have done much, much worse.