When the new Python was introduced I believe the old Python values took a big hit. I see a lot of nice old Pythons at gun shows and none ever sell over the low to mid teens. I confess to buying a new one at a good price but would not pay the same $ for an older one.
I think as the new Python gets further into circulation, prices on original models will drop, but not universally. Shooter grade originals will come down from the stratosphere, but the unique models - as with any brand, will continue to command a premium. Then there is the fact that since no "new" original models will ever be made, originals will retain some amount of premium on into the future.
As I read through various posts I see a lot of comments about "need" when it comes to choosing this brand or that, usually with a bias toward S&W brand revolvers (and why not since this IS a S&W forum!), but let's be grounded for a few moments here: NOBODY "needs" an expensive revolver, they buy it because it appeals to them on various levels. I own a bunch of S&W revolvers and plan to own a lot more, but I also appreciate the "look" of the Python, and all that goes into it to make it such a conversation piece. Unlike a great many it seems, I wasn't terribly impressed with the original. Sure my 4" blued model had "the look," but I wasn't particularly impressed with its double-action as I expected it to be much, MUCH better. Since I didn't pay an arm and a leg for it I didn't feel it was a bad choice, just not in any way so far superior to a Smith to justify the hype...but that's precisely what hype is isn't it.
I find the NEW Python be everything the original was not. The fit and finish is far superior, and in function it indeed delivers an amazingly smooth, light DA trigger pull, and the SA pull isn't nearly as bad as the "internet hype" would have you believe. A tiny hint of creep, and I mean just the barest hint, followed by a crisp release that doesn't jar the sight picture at all.
The DA pull on my S&W M25-15 New Classic is very close to my new model Python. Very smooth, non-stacking (to my finger), and light, but not even close to the butter-smooth pull of the Python! SA let off on the M25 is absolutely crisp with zero creep - "better" than the Python IMO. Now, if all I had to compare was my S&W M69 L-frame .44, I'd rate the Python as light-years better because the L-frame has a rather stiff, heavy DA pull, and equally stiff SA cocking force, though it does have a clean break in SA. Overall the action on my M69 kind of sucks when compared to the M25 and the Python, and it's not as if the M69 was particularly "inexpensive" by any means.
Nobody "needs" an expensive revolver in the .357 magnum power power spectrum, what with a Glock 10mm the ballistic equal at $600, with 15+1 on tap before reload with 26! And while I don't rate the trigger as equal, it's "good enough," and can be made surprisingly smooth and clean with a few "drop in" parts and polishing of contact surfaces. So as much as I love my newest Python, if the SHTF and I had to pick just ONE handgun to journey forth on foot, the Python, and all of my full-size revolvers would probably be left behind. The J-frames would make the journey for sure, but my FN Five-Seven or G17 in 5.56x24 would likely be the choice riding concealed for AP use.