Would you pay a premium for a prewar complete set(subset)

[darwinbulldog]

I think, as the OP suggests, it's largely a function of how much the cheapest cards are worth. For a 1979 Topps set, with commons worth $0.01, you get a discount for buying the complete set. However, when I've seen auction houses offer a set both ways simultaneously (set break into individual lots and a single lot for the complete set), the higher price has generally gone to the complete set rather than to the sum of its parts. I wouldn't expect that to happen with, say, 1934 Goudey in VG or T205 in Gd, but if the individual commons are worth $50 instead of $15, I think that's enough for the bulk discount to evaporate and indeed for the discount to flip over to a slight premium.

But it would be interesting to see what would happen if you hit the territory of a set worth millions of dollars. That might shrink the pool of potential bidders enough that someone could pick up a complete (524) PSA 5 T206 set for less than the cards would have brought as 524 separate lots.