I have a relatively new GX7 and, GAS not withstanding, I don't plan "upgrading" any time soon. My very modest kit is the venerable but excellent IQ/operating value 14-45 OIS zoom (and it's functioned very well indeed as my general walk-around lens on two European holidays), and a new 15mm f/1.7 PL Summilux which so far has been splendid and is currently mounted on the GX7 as my default, i.e., "grab and go" lens. From time to time on a few outings, particularly to the zoo and other mostly outdoor activities, I'd like a little bit longer (than the 14-45) lens option, definitely an OIS Lumix, but not one of the several costly options. I've thought about the Lumix 45-150 which seems so far to be a good value for its IQ and price, but is not sold separately locally. I more and more prefer to buy locally than deal with the possible hassle that might be involved with any returns, shipping, etc even with a solid online retailer like B&H, from which I've purchased in the past and from which I continue to purchase smaller items like spare batteries an, especially, printer ink. I'm wondering if a sensible option for me would be to sell or trade in my 14-45 and substitute the newer 14-140 zoom for both my basic zoom and a 45-150 OIS zoom, or would I suffer an overall IQ and/or operational step backward in the 14-45mm range if made such a change?