Ok, I just love the GRD I for street photography. I know, I said it before but there is no better camera out there. The JPGs at ISO 400 and 1600 look great, grainy but very crisp and with lots of detail. The huge depth of field and instant shutter release are also very helpful and allow me to look for photo opportunities and compose my shot rather than worry about various things. The GRD I never gets in the way and I can rely on it to take the shot when I want to.
Having both the GX200 and GRD I with me in HK is great as it helps making clear what I really want and expect from a camera.
HK is great for street photography and especially in the evening you can get some great shots. I can only recommend you walk around and step away from the main roads and into the dark and narrow side streets, this is where you get some great shots of people and the gritty stuff :).