I've owned several iterations of both over the years including a Dan Wesson .44 mag for variety. For field use the SB is hard to beat because it is compact - or can be with a shortened barrel, and can tolerate some mighty stiff loads without coming apart. The SB also has great pointing characteristics and a fine trigger release. For anyone raised on single actions, a single action revolver can be fired almost as fast as a DA and with greater accuracy. Also, persons trained...or perhaps I should say "raised" with a SA in their hand have well developed manual dexterity when it comes to two-handed, rapid-fire shooting using the off-hand thumb to cock the hammer...a VERY fast technique that makes every shot as accurate as the person can be. There is one major downside to the SA revolver...they are slow to load and reload. Again, for field use where one shot is most often all that is needed, or even against a dangerous animal where time is of the essence. Basically if confronted by a Mt. Lion or Grizzly at close quarters one is only going to have what's in the gun period....whether SB or M29.
The real...and really ONLY advantage the M29 has over the SB is the swing-out cylinder and DA mechanism. I said that as if such is not really a big deal, but unfortunately it is. The original Colt SAA was eclipsed early on by the Schofield for very good reason...the Schofield could be loaded MUCH more quickly - even on horseback. Certainly we form nostalgic attachments to certain guns, but the fact is, humans have always been motivated by the latest technological edge when it comes to weapons..and that is what these items in fact are.
The M29 can be loaded very rapidly, and more rapidly using a speed loader. It can be cleared instantly. It CAN be fired DA which has its time and use, and in the hands of someone who has mastered the DA pull-through deadly accurate at any range where it might be "required."
Even in the field, if jumped by a bear and one ends up sitting in a tree with an empty gun, the M29 can be recharged more rapidly. And of course for those few who still choose to carry a powerful revolver over a "so-so" power semiautomatic, a short-barrel M29 is pretty concealable and will do a very credible job as a defensive option. The SB would do as well for all LIKELY encounters, but this brings us back to the human preference for technological superiority....the DA has it.
As for recoil, SA guns do tend to "roll up" in the hand during firing unless fitted with a high-tac synthetic grip which will make it "kick" more like the M29. The M29 has a grip curvature intended to keep it positioned in the hand which reduces the perception of the gun's muzzle going skyward, but at the same time focuses a great deal of recoil force into the web area of the hand. It all boils down to how one trains, what one prefers, and how one develops the specific "muscle memory" of handling a particular gun.
I've found the M29 Mt. Gun to be highly controllable during rapid DA fire albeit at the "cost" of heavy recoil into the hand...but in a real-life situation that would not even be noticed. At the same time I've taught myself to fire a 4-5/8" barrel Ruger Blackhawk .45 Colt stoked with .44 magnum level loads...VERY fast and with great control...same for 5.5" and 6" "chopped" SB's stoked with heavy loads, but after all the firing is done, the M29 can be recharged more quickly.
I must add a few points though. Because the SB cylinder stays in place there is no opportunity for contaminants to get into the works and bind up the gun. On ALL swing-out cylinder guns the potential exists for shooting debris to get trapped between crane and frame and prevent the gun going fully into lock and thus firing. TRAINING can minimize this potential.
Another point: A SA mechanism is hammer cocked...meaning the cylinder also rotates off the hammer's movement. A DA mechanism is "trigger cocked" meaning the cylinder revolves off the movement of the trigger...and this matters.
Every DA revolver has two points along the trigger stroke where bad things can happen. A short-stroke on the trigger can cause the cylinder to rotate while the hammer remains at rest. A slightly shorter "short-stroke" can cause the trigger and hammer to connect at just the right point to cause the entire mechanism to "jam." If this jam is induced "lightly" as would be done to illustrate, no harm done. If on the other hand this jam were to occur during the kind of adrenalin stoked finger force during a life-and-death situation, the gun could be rendered inoperable. BOTH of these design flaws can be easily and repeatedly demonstrated and what every person who carries a gun for potential combat should bear in mind is that during the "fight or flight" response, fine motor coordination evaporates while gross, "power" motor movements are enhanced. When firing a DA revolver rapidly while in fear of dying, it is indeed possible to "ham-fist" the trigger, causing it to short-stroke at the right point and bind the action.
THIS cannot happen on a single-action, which is probably why so many "old timers" still prefer the SA for "field use." It might be slower to load but it cannot be jammed by any external action of the shooter. Obviously this type of jam would be more likely to occur with a large revolver and longer trigger reach combined with smaller hands.
The way around it for combat use? Train to fire single-action...same, two-handed, support-hand thumb-cocking...this avoids all the mechanical pitfalls of the DA mechanism. One still has the benefit of the rapid reload.