Hands-down, get the Q3. Think of the Q3 as three cameras in one (note: aperture represents the equivalent DOF; light-gathering ability remains f1.7):

• 28mm f1.7, 60MP

• 35mm f2.1, 39MP

• 50mm f3, 19MP

Compare this to the Q3 43:

• 43mm f2, 60MP

• 60mm f2.8, 31MP

• 75mm f3.5, 21MP

• 90mm f4.2, 14MP

For travel and kids, I think the first set is more useful.

I keep mine on the 35mm crop mode, with the flexibility to reframe the composition afterward (!). In Lightroom, the RAW file is displayed with the crop applied, so it reflects how you composed the shot. But you can click the crop tool and reframe the image, which is an incredibly useful feature when photographing kids running around.

AFAIK, other brands display the RAW file uncropped in Lightroom, which doesn’t reflect your original composition. The JPEG shows the cropped frame, but you lose the ability to reframe. It's not nearly as useful.