[tonyo]

I believe your thought about sov460 prices being dragged down a bit since sovs as a whole are relatively common. That said I also believe they are far from scarce.

I'm attempting to build my monster such that the number of each back in my 520 roughly mimics the percentage of the actual backs in existence.

With very limited effort and no original research (borrowed some numbers from Scot Readers inside t206 and Bill Browns superset spreadsheet- thanks for all your effort guys !), I arrived at the following number of each back as my goal for my 520:

sov150 (8-11)
sov350 (19-22)
sov460 (4-6)
pb (26)
epdg (5-8)
tolstoi (6-8)
cyc350 (5-6)
cyc460 (1-3)
ab350 nf (1-4)
ab350 wf (3-11)
ab460 (1-4)
hindu brown (3-7)

Tony