I have about 5 S&Ws for every Ruger revolver I own. If I were to have all my revolvers burn up in a fire or get stolen (God forbid!), the first gun I would get would be a 6 inch GP100. Smiths, though wonderful pistols, are just too much money for what you can get in a GP100. Plus, no internal locks or MIM parts on a new GP100. Not that either are a big deal to me, I have several Smiths with both, but the fact is that the Smith aren't 100% stainless steel and will rust more easily than a Ruger. I prefer no internal lock for aesthetic reasons.
If you could find a used, older 686, for a reasonable price, jump on it. Otherwise, if buying a new gun, definitely a GP100. Ruger is currently stocking a 3 inch, fixed sited gun.
-John