As someone who has just recently begun shooting 4x5 and very much a learner, how many use such packs? I can see the value, that is a preview, but seems a bit like instant gratification, something I've come to dislike about the digicam. One the other hand, while still learning, it seems more logical. However a Fuji holder looks like it retails for $200 which seems like a lot for something that might be used temporarily. Anyone care to chime in with thoughts or opinions?