Look on the inside.
I have owned a couple of Smiths and my friend owns a S&W 500 which he loves. I own one Colt double action revolver and several Rugers (SP101s, Sixes, GP100, Redhawk and Super Redhawk and three Dan Wessons (having stupidly sold my pistol pack a few years ago.)
Of 44 magnums, I have Redhawk 5.5" and 7.5" and Super Redhawk in 7.5" and Dan Wesson 8". My "N" frame Smith (same frame as the Model 29) was chambered for .357 Magnum.
Thanks for asking our advice. Here are my thoughts:
I have found S&W to have generally better double action triggers than Rugers. Single action, the difference is not so noticeable, but S&W gets the nod there, too. That is box stock. Polishing the action can do wonders for any gun.
But I prefer Rugers. Here's why:
I owned two S&W revolvers in my past. Model 28 6" Highway Patrolman .357 Magnum and a K-22 Masterpiece 6" 22 rimfire. When I took the sideplate off the .22, I saw all those small parts inside (comparing it to my Dan Wesson, which had about half the number parts as the Smith.) I lubed the inside lightly, put the parts that sprang out back in and never opened it up again. I traded them off shortly thereafter. The Dan Wesson, in addition to having fewer parts, seemed to have more robust parts as well. Ruger parts are even more robust than the Smith or the DW. I like that.
Undeniably, the Smiths are beautiful guns, but Rugers have their own style of beauty. And, "Beauty is as beauty does." However, My Dan Wessons have lock times that other guns can only dream of.
Nobody seems to ask about Colts, especially their snake series (Diamondback, .38; Python, .357; Anaconda, 44). I have a Colt Trooper (.357 Mag) with a double action trigger smooth as warm butter and better than any of my Smiths or Rugers. None have had any action jobs.
Springs. The Rugers use coil springs. The Smith uses a single leaf as the mainspring. Coil springs are more durable. The Ruger Redhawk's lockwork is unlike any other revolver ever made. It uses a single spring to power the hammer AND the trigger return. This may make it a little harder to tune than a gun with separate springs, but if you like a unique gun, it is one. The Ruger GP100, Super Redhawk and SP101 use coil springs, too, but a different lockwork than the Redhawk. Ruger Sixes (Security Six, Service Six and Speed Six are Ruger's first double action revolvers and are quite strong .
Ruger's Super Redhawk's action is also different, going back o separate springs for trigger return and hammer.
On the strength question, about 25 years ago, S&W made a big deal about the relative merits and strength of forged frames (S&W) vs investment cast frames (Ruger). Yeah, forged has an edge in strength-to-weight and strength-to-size ratios. But that edge has shrunk and, considering Ruger's frames are one-piece frames without sideplates, the design was always inherently stronger (opinion alert). And Ruger doesn't just make Ruger guns. They make frames for other gunmakers and investment cast parts for many other industries. Bill Ruger was a pioneer in investment casting post-war and Ruger still is a player in the industry. Meanwhile, many S&W parts are using MIM Casting technology. Go figure.
Anyhow, a little extra weight has its own advantage in a heavy-recoiling gun.
Happy shooting.
Lost Sheep
p.s. Don't get the Redhawks mixed up with Blackhawks (Regular or Super versions) Blackhawks are single action. Redhawks are double action.)