This thread
http://forum.lugerforum.com/showthre...flation&page=2
began from a financial perspective but also discussed future appeal of the Parabellum.
Since participating in that thread a few years ago, I'm overall still of the opinion that Lugers tend to appreciate at or slightly above the rate of inflation. Demand probably dips and inflates with ebbs and flows in the economy, climate for firearm regulation and so forth but overall is pretty stable.
Phrased differently interest in the pistols will continue for the foreseeable future. The supply of original pistols remaining is finite and always decreasing due to wear and oxidation. The history, aesthetics, uniqueness of the action and other factors are IMO too compelling for these to ever fade into so-what status.