I recently bought one of these to see what all the fuss was about 1" sensors
I was surprised by the size of the camera but it's no larger and possibly a bit smaller than the 35mm compact cameras I used to use. One thing which I'm pleased with is the on / off switch as my previous Panasonic compact was an LF1 and it was just too easy to turn it on accidentally.
I find the TZ100 files a real step forward in image quality from the LF1 which shared the same sensor as the Panasonic LXx and I like the zoom range and the only complaint I have at the moment is the rather ordinary aperture range, no doubt a price to be paid for the zoom range. I'd say that the image quality isn't a match for micro four thirds but is definitely a step up from the smaller sensor quality compacts like the LXx range which were as far as I know considered to be about the best in class.
One thing I'd like to comment on is the dials and setting the aperture, shutter speed and exposure compensation. I read one review in which the reviewed complained that in manual mode there was no way of changing the aperture but this is simply not true as shutter speed and aperture can be assigned to dials and a press of the top button of the control pad enables exposure compensation. Simples
I use mine in aperture mode until the shutter speed drops too far and then I switch to manual mode, dial in the aperture and shutter speed I want and let the auto ISO float. Actually I use the camera mostly with the lens wide open and only stop down occasionally. Zoom wise I leave zoom resume on and set to 35mm (equivalent.)
I think that this camera and other similar ones make very good day out and holiday cameras. I recently took mine to Thailand along with my Sony A7 and 35mm f2.8 and used it for wider and longer shots and for silent shooting and when I thought that the A7 was inappropriate to use and I have to say that it worked very well. I shot some comparison shots side by size with my A7 and I might just post them later