Is there any reason except weight and price for which one would choose the 40-150?
The 40-150mm is optically better and lets you open to F/4 at 40mm, while the 14-150mm is already F/5.6 by that focal-length, so you get more light in until you get close to the end of the zoom range.
For sharpness, it depends which side of the 40-150mm range you prefer. At 40mm, the 14-150mm is noticeably sharper than the 40-150mm. At 150mm, the 40-150mm is noticeably sharper. See sharpness samples at all F-stops here and here
Vignetting is terrible on the 14-150mm at both ends of the zoom, while moderate on the 40-150mm and only near the widest aperture. The 40-150mm lens also shows less distortion.