Please do not read any meaning into what I am about to say, just take it exactly as it is presented.
While the long cylinder Smith and Wesson cartridges (both the .460 and the .500) are tremendously powerful, here are a few things to bear in mind.
The .454 Casull can and has taken the largest game animals on the planet and done it humanely. The limiting factors are shooter ability and bullet construction. Keep in mind that .45 caliber pistol bullets, particularly lighter weight hollow point types, are not designed to perform at the velocities that the .460 is capable of. This can lead to explosive expansion and fragmentation, resulting in shallow penetration.
When hunting large, tough animals, a non-expanding bullet is often the better route to take. While the .460 will still drive any given bullet weight to higher velocities than the .454, this is of limited value. You wold be hard pressed to show that a through and through wound from a .460 differs to any appreciable degree for the same wound from a .454. The .454, and even a stoutly loaded .45 Colt will shoot all the way through the majority of game animals on North America, and deliver clean kills with proper bullet selection and placement.
As I stated earlier, the .460 does indeed outpace the .454, but how much advantage is this? Inside of the ranges that an average shooter is capable of engaging game animals humanely, the .460 will shoot flatter. This does make longer shots a little bit easier. There are some pitfalls to this as well though. because the path of a bullet in flight is a parabolic arc, as the target gets farther away, the amount of compensation for bullet drop increases at a much faster rate. You must not only know exactly how far away the target is, but how much drop your bullet will have at that range. You can use all the latest computer programs to calculate this that you want to, but unless you have a chronograph, and spend time on the range verifying computer predictions, all you are doing is guessing. Keep in mind that atmospheric conditions will alter performance also. Testing in the summer in the Midwest is of little use when trying to make long shots in the mountains during winter conditions.
Now consider the size of the guns available chambered in .460 S&W. All of them are large frames to accommodate the long cylinder. Most of them have barrels of at least 7 1/2". Weights seem to range from about four pounds to nearly seven pounds. Add a scope to it and you gain another pound or so. You are at or near the weight, maybe even exceeding that of a Marlin rifle chambered in .450 Marlin (S&W lists the weight of the .460XVR as 82.5 oz. or 6 7/8lbs. Marlin lists the weight of the 1895M as 7lbs on their websites).
As for the ability to shoot three types of ammo, I'm not particularly a fan of this practice in guns that will accommodate it. Using shorter cartridges can cause buildup at the in front of the case that can lead to a variety of problems. The most noticeable is not being able to chamber longer rounds without first giving the gun a good cleaning. A more serious problem, because it can go unseen until the damage is done, is that it can cause pressure spikes due to the seating of a longer cartridge against this buildup. Granted, people have been doing this for years with .357 and .44 mags, but bear in mind that these cartridges operate at much lower pressure than the .460s 60,000psi. A pressure spike at these levels can be catastrophic. Don't take my word for it though, call Freedom Arms and ask why they do not recommend this practice in their guns.
The last item that I will address, in this ridiculously long post, is recoil. Recoil with the big boomers is severe. Anything in the performance range of .44 mag and up generates enough recoil to cause physical damage to your body over a long period of years shooting heavy loads. Wrists and elbows are particularly susceptible to this damage. Increase the recoil, and you increase the potential damage. Once again, don't take my word for it. Go over to Singleactions.com or the Gary Reeder forums and ask John Taffin about this. If you don't know who John Taffin is, how dare you call yourself a handgunner?!
As I said at the beginning of this post, please do not read something into this post that is not there. None of this is meant to talk you out of purchasing a 460, or to demean the cartridge in any way. It is only presented with the goal of providing thoughts that may help you make a well informed decision. The 460 is an awesome powerhouse with performance to spare. If it tickles your fancy, by all means, go out and grab one up!
JW