I have not tried the G2 but generally I find that any dependency on batteries, or auto settings in a camera, really gets in the way of taking pictures for me.
I would probably do so with a Bessa body like the R3A, and add my lenses in the same incremental way.
I stand corrected - the Bessa R3A does have an electric shutter - I had in mind the Bessa R2 which of course has a fully mechanical shutter, and only uses batteries for the metering.
I still stand by my comment about lens choice though - the Contax lenses might be nice and compact, but you are really lacking choice particularly with regard to large aperture glass.
In terms of useability - it is down to whatever floats your boat. I am not looking to start a holy war - in the end whichever camera you use, it is just a tool to make pictures.
BTW, the G2 (not the G1) has active IR. When using it at night, it will focus in complete darkness over a limited range. Kind of a weird experience sometimes if someone is walking toward you in the dark (or vice versa) and they cross over from >3m to <3m and SNAP the focus locks.