With the launch of the Q3 there seems to be a bump in the used Q2 availability. They maintain their value pretty well so you can conceivably buy one now, use it for a good long while and not incur too much of a hit if you decide to sell it.

Same lens in all Q models. Most would be hard pressed to tell the difference between images between any of the Q models online.

Hardcore Leica fans do praise the controls of the Q cameras. I like the macro mode and I the well damped feel of the focus ring and aperture ring but would rather have the dedicated shutter speed dial and ISO dial a la the X100x cameras.

That said the top control wheel that is changeable with a quick push isn't bad. I toggle between exposure comp and ISO with it pretty fluidly.