I think eventually the VB unc will command the highest price, with the Jackson unc not too far behind. Given that, I think the Buchanan is the one to buy on the cheap right now, greysheet has it at 1025 bid but apmex had them on sale for about $950 until yesterday. Much rather go with that than speculate on the newest low mintage ugly. Though other spouses may finish at lower mintage, Julia will always have some appeal because she is not ugly (on the coin that is).
I don't know how many VB uncs I have, several but whatever it is, not enough.