I have found the various Olympus kit lenses I've picked up along the way to be of very acceptable quality and IQ. Often as good as high grade lenses on larger sensored cameras, or better ... !
I do not count my FTs 14-54 MkII or my 12-50 macro as "kit lenses", even though both came with the E-30 and E-M1 MkI as a kit, respectively.
While the kit lenses are not in the same class as say, my FTs 7-14, 11-22, 14-54 MkII or 50-200 MkI, or my mFTs 8-25, 12-50, 12-100, they have been used to take some quite stunning photos (IMHO). Some of the best photos I have ever taken in a photographic life of some 63 years, using all sorts of cameras up to 5x4" format. I have printed a number of these at A2 size (17x22 inches) on my Epson R3880.
While I've never owned one, the 14-150 MkII seems to be "good enough" for many shots, and very versatile, like the 12-50 macro. A (relatively) cheap, WR general purpose lens that doesn't cost a kidney. A noticeably better IQ than the FTs 18-180, which was occasionally OK, but often unacceptable.
A quick review by Imaging Resources here:
Find out what 3 readers thought of the Olympus 14-150mm f/4-5.6 II M.Zuiko Digital ED in our review.