Michael,
Thanks for that. How do you shoot at night - do you use manual or auto focus? I'm guessing you're shooting pretty close to f1.9, so the DOF isn't nearly what it is in good light, so you might not want to rely on hyperfocal or zone focusing? My experience with the LX-5 is hyperfocal is wonderful for good light shooting, but when the light it low I end up using the AF, which slows the whole operation down a fair amount. And I'm wondering how that works on the GRD3? Out of curiosity, have you tried the LX-5 (or LX-3)? They seem to have some of the same strengths, but of course they have a zoom lens, so probably not quite as sharp at the 28mm setting. Also, if you're turning off the LCD, are you framing on instinct or do you use an add-on OVF?
I have an LX5 and I'm having trouble seeing what the GRD 3 would improve on, but if you've used both, I'm curious. I'm having very mixed feelings about the X-100 and if I don't end up with one of those, I might look at a GRD...
-Ray