don't know how true it is but I've had at least 2 different gun dealers tell me the 500 S&W's felt recoil is less than the 454's. Has anyone shot both and agree or disagree?
Yes...no...maybe. When comparing recoil it's critical to compare apples to apples, and even then there are a lot of subjective points to consider.
I've fired many rounds with my Ruger SRH .454 Casull, and a couple weekends ago I had the opportunity to shoot several rounds through several of the various S&W Model 500's, and I'd say that my perception of relative recoil depends alot on which gun you're shooting and the load.
For instance, my RSRH (7.5" bbl, no brake) shooting 300gr loads is one heck of a handful compared to the 6.5" M500 Performance Center revolver with 325gr factory loads. The Performance Center barrel has a very efficient brake and tames it down a lot, and the pistol still has some mass to it. With the 440gr Corbon loads this same 6.5" M500 womps you a LOT harder than the Casull, and on top of that the muzzle blast sounds and feels like a 155mm Howitzer.
Comparing my RSRH to the 4.5" M500 with standard brake, well, there is no comparison. 325 or 440gr loads from the M500 both rock your world a lot harder than even the hottest .454 Casull loads I've shot, both in the felt recoil and muzzleblast department. I was wearing 33dB muffs and that damn thing still rang my ears. S&W touts the 4.5" M500 as the ultimate bear country defense gun, but I'll tell you one thing is sure. IF, and that's a big if, you hit the bear even halfway decently with that thing you'll drop it like a bad habit...the bad news is that you might spent the rest of your life responding to others with "WHAT?"
I also shot the 10" Performance Center M500, and it was a ***** cat relative to the top end .454 loads, but still kicked a bit harder than the lighter 240-250gr .454 Casull loads. Of course, the gu weighed like 6 stinkin' pounds, with all of it toward the muzzle, which helped a lot.
I will say this seriously, though. The M500 DEFINATELY has better stock grips than the Ruger SRH. The M500 grips cover the backstrap completely with rubber, which really helps reduce the punishment suffered by the web of ones hand. The SRH's grips don't completely cover the area and with hard kicking loads that backstrap can come back and bite you good. The M500 also benefits a great deal from the brake, perticularly in the muzzle flip department. My Ruger's muzzle comes up with authority, where the M500's muzzle kicks more straight back. I would DEFINATELY NOT want to shoot the M500 without the brake installed, especially with 400gr+ bullets at near max loads. I can say for sure it'd be a real butt kicker without it.
Overall, I was very impressed with the quality and shootability of the M500, but my .454 Casull will do everything the 500 S&W will do, in a gun that costs $200+ less. 500S&W factory ammo is also VERY EXPENSIVE, even compared to .454 Casull, so if you don't handload you're going to probably spend more in the first year on ammo than you did on the gun if you shoot it enough to get proficient with it (just because it may feel a bit less than the 454 in the recoil dept with certain variants and loads, that doesn't make it a lightweight by any means. This is a gun that will take almost anyone a lot of range time to master). I also like the ability to shoot .45 Colt in my gun if I'm not feeling masochistic when I go to the range!
Bottom line, the 500 S&W is a bruiser, and so is the .454 Casull. Get the one that you like the best and/or you can afford. Both the Ruger SRH and the S&W M500 are great guns, with a small nod to the M500 in the quality and fit department, and both will serve any hunter well. I just personally can't afford the cost of the gun, and IMO the features the S&W has over the Ruger are too small to justify over $200 bucks more money. For $200 I can buy an set of Pachmeyr grips, holster, loading dies and components to load the first batch of 454 ammo. Both will kill anything just as dead, and both will do the job humanely to any reasonable pistol range.
Which you choose is up to you...
Mike