While I can say with confidence I don't need any other lenses I really have a hankering to pick up a wide angle zoom. My short list of requirements: Has to be wider than 12mm No fisheye - I have the 8mm 1.8 pro and it is a great but there are limits to the perspective. I've had the 9-18 f4-5.6 and I might consider another one. It is light and compact. I really like the 8-18 Panasonic but I am little worried about the quality. The 7-14f2.8 is a great lens but the lack of easy filters mounting and the relatively short long end limits the versatility.