Any gun/ item may be considered rare if there are only a few in existence. That doesn't make them valuable. People confuse rare and high value as synonymous. That is far from the truth. To be valuable there has to be a market that is much larger than the # available. (real or perceived that drives up the price) I saw today where they are selling a 1971 'Cuda that is 1 of 2. It is rare but also valuable as there is a large market for that car. It will go for $1.5-$3M That is $3,000,000! But a 2nd gen semi auto... no matter how rare..has a very vey small market. MY LGS sold me a LNIB 669 last year for $250 OTD. No value as no market. Now in the S&W world...a registered magnum will bring thousands. There were several thousand made but they have a market that will pay for their rarity, provenance, (many were owned by famous people) And they could be custom ordered.