4x10 - 12 holders - 6 AWB wood & 6 Canham.
8x10 - 24 Holders - Fidelity.
7x17 - 6 Holders - AWB, and saving for 6 more?

I like having enough holders to load a full box (-1).

I always take the 8x10 and one of the Pano cameras for a trip and hate to change film during the trip.

Scott