I'm really, really late to the discussion on this one, but I do like the set, and I can see your reasoning to consider both the Red Backs and Blue Backs as part of the same set, especially because the cards say "Series A" and "Series B". But, I also like having it separate precisely because both sets are numbered 1-52.
What bothers me more is the voting. Sure, the 1951 Bowman set looks better, and I'd vote it higher, but the Topps 1951 Red and Blue Backs are important. I probably rate it higher because of that. If it were a subset put out in 1965, for the sake of discussion? Well, I'd still probably rate it high. I just like the set.
I wonder if my view of the two sets aren't colored by the fact that they're both "completeable" for me. I'm lacking only a few of the 1963 and '68 sets, but I'm missing the big money Rose (1963) and Bench (1968). I might never complete those sets because of those two cards. I'm also missing a handful of other money cards from 1963, such as Stargell and Yaz. I'd love to complete the 1965 set, and while I have the Koufax, Aaron and Catfish Hunter from that year, I don't have Mays, Mantle, Carlton, Perez, Rose, among others.
Thank you for the discussion.
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