Not bashing Ruger Revolvers and to me they "have their place" in our hobby as less expensive, more crude type of Revolvers and are just not in the same league as the older S&W's which are much more refined. Yes they work, yes they get the job done but they are clunky, rough, have a less conventional take down and are mostly purchased as a less expensive alternative to a Smith or Colt. If all you have to spend on a Revolver is strictly a fixed amount and all you can get for that amount is a Ruger - yup, it will work.
As far as comparing a Ruger Security Six against a Smith 686 (vintage version) - the Smith is way on top IMHO. Just my personal opinion and YMMV.
I looked at on line vendors just now and noted that Bud's gun shop has stainless steel GP100s selling for $663 in stainless steel. Bud's also has stainless steel 686's in the same configuration selling for $741.
That's only a $78 difference, yet you're making Ruger sound like Rossi or Taurus with your "crude", "clunky", "rough", "less expensive", "not in the same class as S&W" language.
I've own or have owned four Ruger DA revolvers:
- 3" SP101 in .357 magnum;
- a 4.25" SP101 in .22LR (that I returned to the factory and then sold the replacement because it was still ****);
- a 4" Service six in .357 Magnum;
- a 2 3/4" Speed Six in .357 Magnum; and
- a 6" Security Six in .357 Magnum.
In comparison I have a few more S&W revolvers and I'm obviously biased toward S&W and in particular pre-lock model number S&Ws:
- 5" Victory Model
- 4" pre Model 10
- 6" K-22
- 3" Model 13-3
- 6" Model 14-3
- 4" Model 15-3
- 6" Model 17-4
- 6" Model 19-4
- 4" Model 19-5
- 1 7/8" Model 36 (no dash)
- 1 7/8" Model 36-10
- 2 1/8" Model 60-14
- 3" Model 60-15
- 6" Model 66-2
- 2 1/2"Model 66-4
- 2 1/2" Model 686-5
All but three of the above revolvers are Model number revolvers, all but three are "pre-lock" and most are "pre-MIM".
I agree with you that the GP100 is "clunky", but then so is the full underlug 686 series, compared to the earlier Model 66. The only 686 I own is a 2 1/2" where the difference between its full under lug barrel and a shrouded ejector rod 2 1/2" barrel Model 66 is minimal.
I also agree that Ruger fire control parts from the Six series forward have been larger than S&W fire control parts, and they have always been MIM parts. But they are very durable and looking at my S&W and Ruger revolvers in total, the Ruger trigger pulls on average really are comparable on average to the S&W triggers.
Quality wise, the old Ruger Six series were on par reliability wise to the S&Ws of the era. The S&Ws of the era had a higher level of polish, but the Rugers were built like tanks and almost never broke. The Six series certainly had a stronger frame and forcing cone than the K frame S&Ws.
The current GP series frame is still stronger than the side plated L frame revolvers. Ruger's take down is different, but it was done that way to allow for a stronger frame with no side plate. Ruger also offset the bolt in the frame, and the notches in the cylinder so that they do not create a thin spot on the cylinder, something you don't see with the S&Ws until you get to the 686.
In short, you can't accurately state that Ruger DA revolvers are not in the same class as S&W revolvers, and you certainly can't dismiss them as cheap, or something usable for the teaming masses, but not appropriate for the more refined shooter who obviously should be shooting a S&W.
They are in the same class, but simply reflect slightly different design objectives.
In terms of quality, IMHO neither S&W nor Ruger makes a revolver to the same quality they did in the past.
MAYBE THAT'S WHY it's called DOUBLE ACTION ONLY. 
