I agree with Ron on the relative commonness of the blank backs - they're much more common than I thought when I first started collecting T207. You don't see them everyday, but they're common enough that most that want one have an opportunity.
One other thought on the jump in valuation based on back, speculative or not. I think there's a big difference in the starting point when compared to T206. Rare backed commons being had relatively cheaply in T206 not so long ago meant (and I'm guessing, because I was also not collecting then) in the low 10's of dollars, and now they're many times that? Maybe an influx of more collectors or speculators will change that, and there'll be more upside potential. Given the relative interest in T207 - many just can't get past the design - I can't see a bandwagon of folks flocking to the set to make a rare-back run on T207 likely for a variety of reasons:
- For the T207's - even in the tough economy - Broadleaf class cards will often start *way* above what a lot of people will pay, so big upside is tough - margin through bulk is hard work, and there aren't that many cards (or interested parties).
- At the end of the day, all four Broadleaf class (BL, Anon3, Anon25, and Cycle) backs have the same sets of player/poses - they all appear with all 50 cards, likely all 51 if you include the Lewis variation). There's not as much innate interest generated in that, when compared to the mysteries of T206.
- Other than Broadleaf, they have similar distributions, though Broadleaf is probably 2-3 times more common than the others.
- In general, all those cards are tough, significantly moreso than most Recruit cards. "Rareness" comes along for the ride - variations in that are moot.
- T207s are generally perceived to be much tougher - in general - than T206, whether or not that is numbers produced (likely), relative survival rate (?) or whatever, they're simply tough to start with.
I reserve the right to completely wrong on everything I've written.
, but by simply collecting T207, you're already in minority of the card-collecting population... some would say that enjoyment is its own reward.