T206 back scarcity question

[inceptus]

Hi all. I've been an active collector since I was a tot back in the early '70s, but I've only picked up the prewar habit over the past several years.

I've found some great resources here and elsewhere regarding T206 back scarcity, but I had one lingering question.

I see that most resources rate the Sovereign 460s as relatively scarce, harder to find than variants such as brown Hindu, Cycle, Tolstoi, EPDG, and American Beauty. However, based on my limited observations and a scan of price histories, it appears that these sell routinely for less than many of the other more "common" backs listed above.

So are the Sovereign 460s indeed scarce, and their value just hindered by the fact that they are simply variations of a relatively common back, and thus less interesting aesthetically, or is there something else in play here?

Thanks in advance for indulging a noob's curiosity...