The Electric Sun is the most picked pledge level because it is new content, so getting it in print and PDF makes sense. I think there are lot of people, me included, who would like to get Invisible Sun Indigo in PDF only as an add on because they already have the original Invisible Sun in print. Can you make that an add on option? At the moment I'm considering either getting Invisible Sun Indigo PDF only pledge level while waiting for The Electric Sun to drop in your store, or getting The Electric Sun print and PDF pledge and opening a second Backerkit account so that I can also do the Invisible Sun Indigo PDF only pledge level.