First, I'm not a mint-crazed collector. Sure, if I can get a card in great condition, I prefer that. But it's not the be-all end-all. The farther back I go, the more lenient I am on condition. And, if I'm going that far back (1939), I'll take almost anything. I tend to look for graded vintage cards for authenticity sake. And, where I'm usually looking for about a 5 on a card from the 70's, I'm happy with a 2 for a super vintage card or a big star from the 50's. My '53 Paige is a 4. My 1911 Evers is a 2.5. They're both about a grade higher than I would have accepted. I'd love a 1911 Walter Johnson, and a 1.5 would be just fine. Most of it is financial. Part of it is that I almost like the super old cards to look old. I want a tobacco card to look like it was stuck in a box of cigarettes. I want a thirties card to look like it was in the depression. Otherwise, I might as well get the reprint. I'm probably rationalizing, but I almost believe what I just said.
In the end, of course, we all have to make our own calls on how much to spend to avoid a crease or rounded corner. As long as you're comfortable , it's all good.
V3