The lens seems to be parfocal, but during zooms the picture gets blurry for a short moment. This problem also occurs with the Lumix 12-35, but there's one big difference between these two lenses: The 35-100 does not flicker while zooming.
Lens breathing is quite noticeable at longer focal lengthes, e.g. 100mm. At 35mm the lens performs quite well.
The OIS works fine and is strongly recommended for handheld camerawork. If you put your camera on legs, you should switch the OIS off, expecially when panning or tilting at longer focal lengthes.
I did not test the autofocus because I never use it.
After shooting and editing for a while, I've come to really respect both skills. I think more shooters should learn each and learn how to think like an editor when shooter. Check out this tutorial for 7 Tips to shoot more like an editor.
FRAMELINES, in association with the MID OHIO FILMMAKERS ASSOCIATION (midohiofilm.com) present a panel discussion on Producing with local producers Ben Bays, Phil Garrett, and Bo Buckley. Moderator: Scott Spears.