The GF5 offers a Lumix G X 14-42mm f/3.5-5.6 power-zoom kit lens option, which we can't fully recommend. It's a strange lens, many have reported 'double image' issues, specifically at the longest zoom within the 1/160-1/200 shutter speed range, with and without image stabilization turned on. Many have also reported no issue with their lenses, and it appears that a firmware update to the lens late last year may or may not have fixed the issue. A quick glance at Amazon.com reviews of the lens will show you the diverse range of experiences with this lens.
While some users have reported severe image doubling issues, we didn't see it with our review lens. What we did see was image softness/blurriness in some images, similar to what Imaging Resource reports on their shooter's review of the GX1, but not as consistently.
None of the image softness problems surface when the camera is locked down on a tripod, which opens up the possibility that it's the user's shaky hands which are causing the blurriness. We are shooting at the furthest zoom after all, where a slight shake of the hand will cause more noticeable blur. But then we discovered that some shots are actually sharper when image stabilization is turned off - the opposite of what you would expect from shaky hands. Maybe the image stabilization in the lens is not working - but at other ranges, we've found the image stabilization to be really good at producing sharp images from slow shutter speeds shot hand-held.
The amount of image softness we see in our tests is not noticeable unless you zoom in close on the image, which leads us to think that the majority of GF5 users will not be affected by this problem in everyday casual use. However, when compared to the severity of others' images online, it leads us to the theory that there may be a number of defective lenses on the market, and we just happened to receive one of the better ones. There is certainly something strange going on with the image stabilization system in the X 14-42mm lens, and for this reason we cannot wholeheartedly recommend it.
Panasonic has declined to comment on the issue.
It's too bad, because while we weren't crazy about the lens on the GX1, we actually think it's a perfect fit for the GF5. As a collapsible pancake/zoom lens, the X 14-42mm mounted on the GF5 make for a trim combination. We also consider that the GF5 owner will shoot differently from the GX1 owner. The main grippes we had with the X 14-42mm lens were that the zoom toggle took too long to compose compared to a zoom ring - there were no focal length markings to determine where you were before looking through the frame, and that the zoom toggle was too easily confused with the focus toggle. It's likely that the GF5 owner won't mind the first two. The GX1 is a camera targeted towards the enthusiast, who wants everything at their fingertips so that he/she can quickly frame and grab the decisive moments. The GF5 is a camera for more casual use, and its owner will probably have more time to frame the image before shooting.
If you still want to try the Lumix G X 14-42mm lens, we advise getting it at a knowledgeable shop where you can return it if defective (and they understand technical photographic problems like 'image softness at longest telephoto'). If not, you can always opt for the other standard, non-power zoom 14-42mm lens kit.