I am making a 150gig sparsebundle which will be about half full, with more to add in the future. I plan to use Chronosync to backup this disk image to an external drive, but I am curious about the practicality of having a singular 150gig file, and if it will be able to be incrementally backed up, or if every time the backup runs, the entire 150gigs will have to be copied? I know that the sparsebundle works by having smaller files comprise the entire image, but will programs like chronosync, superduper, carbon copy cloner, will they be able to only update the changed/added portions? I can't imagine the wait every time you need to backup or mirror a single 150gig file. Does anyone have any experience with this and how it could be done easier?