There are two versions of the Panasonic 14-140 and they are both much more expensive than the Olympus 40-150. So yes, they are better if you can afford them. The optical quality of the Olympus 40-150 is not too shabby http://www.photozone.de/m43/780_oly40150r?start=2 I've shot sharp videos at full telephoto using the 40-150 with my Olympus E-M5 camera.
Wonderful lens and really a must for that price! (Just 89€ what is a steal, I bought my from sale 139€ what is $188.)
Now I am seriously considering 75-300 II but I am second guessing again.... Ordered it once again but thinking to cancel order. Need to do own thread about comparison.
40-150 R is wonderful but sometimes I wish it would have the extra step. 300mm use to be much on film era and 200mm is even today for many, so 300mm what this lens offers should be enough. If you only pay that $119 for it, it IS a must to have!