It's a really fun lens. Maybe a little wider than I'm used to. I've not used the Leica version, but from looking at images online there's really no difference.

A negative I'd give it is on handling, it's pretty easy to knock the aperture ring as you get it out of the bag. That won't be an issue if you use Olympus/ om though as it only works on Panasonic.

There also apparently issues with continuous autofocus with the early firmware version if you have a camera with phase detect. Then to update the firmware you need access to a DJI drone.