I've had a GR Digital since 2006 and it's possibly the best digital camera I've ever owned.
It's small and light, you can stick it in your pocket and take it anywhere, but it's not flimsy.
The battery holds its charge when not in use, unlike many cameras I've owned which will drain a battery dead within a week even when switched off!
You can configure the camera how you want it, then save the settings. The GRD1 and 2 had two setting slots, I believe the 3 and 4 have three slots. With the GRD1 you have to go into the menus to select which setting you want the camera to power up in, later models have the selection on the control wheel.
I've got mine so that setting 1 is 400ISO black and white 'snapshot' fixed focus, and setting 2 is 64ISO colour.
The problem with the GRD1 is that it's very slow at saving raw files. Mine takes about 15 seconds during which time it shows the last image with the caption "RECORDING". So I just shoot JPEG most of the time.
These are a few out of the camera jpegs...
Texture by
Antony J Shepherd, on Flickr
or, in colour
Autumnal Colour by
Antony J Shepherd, on Flickr
Note that a GRD1 won't take SDHC cards (I just tried that).
Also, mine has started to suffer from the problem where using the Adjust wheel makes the firmware crash, and I need to switch the camera off and on again to make it work. That's something else you'd need to look out for on a GRD1.