I use 4K all the time, and particularly for weddings because some of the frames are good enough to make excellent stills! Also one has the advantage in post of re-framing when one of my shooters screws up! My workflow is to import into FCPX and immediately transcode and make proxy files of everything so I can edit a three or four camera multicam. Its does result in huge amounts of drive space but I have found a relatively low cost method of acquiring that...used Lacie Quadra Big disks which I upgrade with 4GB drives from Amazon or Costco!