Can I ask why the combination? It seems like they all do similar tasks. (Also, it seems like Lightroom could also do all those tasks, but LR is Adobe and maybe you're staying away from that.)
More pertinently to me, as I've been looking for something to replace iPhoto for managing my 50K photos: Aperture uses its own database, and it looks like Acorn at least does as well. Do all these apps play nicely with each other? Would you able to easily have your photos on several different hard drives, without worrying too much about libraries and what-not?
I've been trying to find something that's as easy to use as iPhoto for simply scrolling through photos, but that just treats all my photos as files. So far I've found Lyn, but that seems to be a little too bare-bones. Would love something like that with the ability to sort and tag photos (using Exif, and not a database).