10 out of 10 points and recommendedSharp, even wide open. IS is very good, even on Lumix bodies. Close focusing makes for a very versatile travel lens. OOF areas is very smooth.Larger than some may want, though smaller than the 12-35/2.8 and 35-100/2.8 combo.
There's not really a lot to say that hasn't been said many time over concerning the quality of this lens.reviewed June 12th, 2017 (purchased for $1,299)
Almost all reviewers are mounting it on the E-M1 II which is understandable, but I don't have that body to shoot with. I shoot with the Panasonic GX7 and the GX85. The GX7 has a limited 2-axis IBIS while the GX85 has a 5-axis IBIS. Mounting the 12-100 on either of these bodies results in the IBIS options being grayed out in the camera menus, leaving only the lens IS active. The lens IS is considerably better than the IBIS of the GX7 and has given that camera a new lease on life. I have the J.B. Camera Designs grip on each of my camera bodies which do aid in using a larger lens like the 12-100.
I travel professionally and carry one of the Lumix bodies, the Panny 7-14 with the 12-100 in a small Tenba bag, making for a wonderfully small, quality kit. I have fast primes when I need the speed, but otherwise, the 12-100 @f/4 covers such a wide range of circumstances.
If you are looking for the best travel lens - this is the one. Don't think you have to have the E-M1 II to use it!