The downside:
the filter on the camera needs space, the pocket is so passé, the small compact camera bag also. Is in the nature of things. Handed me previously a Lowepro Apex 60 AW so it now needs a Lowepro Apex 100 AW.
By folding screen of the G12 there is (for me) when it has to be fast also times that I use the optical viewfinder. Here covers the lower third of the picture in wide angle the filter adapter. Is also in the nature of things - so do not scare ;-)
What else would be desirable:
one has to filter permanently on the adapter sets this but only sporadically (because pole, leveling or other non-UV / Protect Filter), so would be a cap for the rear nice, so that the filter from the inside not fully dusted and you the filter holder can use along with fast without much fumbling and Schrauberei.
Time will show, however, I like the holder Use.