Tell the complainers to look at SMR which breaks down the set 1-24 and 25-48.
However, when I completed my set in SGC 84-88, I noticed no difference in availability in high grade between the two series. There are tough cards, Holman and Thorpe, in the low series, and Baer, Didrickson and Seppala in the high series.
Hubbell and Jones in the high series were not any tougher than the low series cards. Just more expensive.