I've got several samples of each of these guns and they're all great guns, just different! I do get a little more sense of pride of ownership with the Smiths, but that's beyond the actual shooting part, which they all do very well. In my experience there is practically no difference in durability of a GP-100 vs. a 686.
If this were my decision and I know what I know now, I'd look for a lightly used, slightly older Smith 686 (pre-lock) with a 4" barrel. Not saying I don't like the GP-100, because they're great guns as welland I'm glad I have a few of them... but I guess the Smith offers just a little something more, perhaps something intangible, that I like. Then, I'd buy a new GP-100 with 3" barrel and fixed sights. Just me.
If this were my decision and I know what I know now, I'd look for a lightly used, slightly older Smith 686 (pre-lock) with a 4" barrel. Not saying I don't like the GP-100, because they're great guns as welland I'm glad I have a few of them... but I guess the Smith offers just a little something more, perhaps something intangible, that I like. Then, I'd buy a new GP-100 with 3" barrel and fixed sights. Just me.