Need a lens for my GH3. I've been looking at these three. #1 LUMIX GX VARIO PZ 14-42mm / F3.5-5.6 ASPH. / POWER O.I.S. #2 lumix g vario 14-42 / F3.5-5.6 ASPH. / MEGA OIS #3 LUMIX G VARIO 14-45 / F.3.5-5.6 ASPH / MEGA OIS These are, to my amateur eye, seemingly very similar lenses, all made by the same manufacturer. When looking at the specs I can't see anything that should make one lens better than the next. Yet, there are some differences in price and weight, and I need your help to figure out why. I want the lens with the best image quality, but if the difference is very small, cheapness and lightness are pluses. The #1 is about $300 and extremely small. It weighs less than 100g. The #2 is only $167 and weighs 165g. The #3 is $300 and weighs almost 200g. Why is the #1 so light and small? Is the zoom not optical? Doesn't it have a manual focus ring? Is there no on/off switch for the OIS? Why is the #2 so much cheaper than the two others? All tips and opinions are greatly appreciated! Thank you.