I’ve had a lot of GRs. Mainly because they are fragile and I return them if they show any lag with the lens motor. I was playing around earlier with my Ricoh GRIII and the GRDIV. The GRIII has a crop sensor with a 2.8 max aperture, the GRDIV has an iPhone sized 4×3 sensor with a 1.9 aperture. I gtta say, after playing around I much prefer the 13 year old GRDIV. It has much faster AF, macro down to 1 millimeter, DOF for days, superior battery life, on camera flash, separate exposure compensation button, 4×3 sensor which is great for landscape and portrait shots and a bit lighter. The ony thing I’m missing from the GRIII is the faster start up time, wider apertures (the GRDIV only goes to f9. This matters as I like to shoot at ISO 1600 to get that sexy grain), highlight weighted metering and more customization in the film effects. The black and white images from the GRDIV are also superior in my opinion. Set it to ISO 1600 and the grain looks killer. Matched with the CCD tones, the black and whites are pretty spectacular. Shooting JPEG only, the files from the GRDIV are around 4mb so big enough for most things.
Have a look at this using the Ricoh GRDIV. Here’s a macro shot of a callous on my hand from pull ups. This was a SOOC BW film effect with contrast boosted to max at 1600 ISO. I used the auto level correction in camera to give it a bit more contrast.
I’m sure people today will discount this camera because it seems we are obsessed with sensor size and megapixels. I’m guilty of this as well, but if you’re just doing this for fun I can’t imagine why you wouldn’t dig the GRDIV.
Chris Athanasiadis 
i wanted to buy it but as you said – the sensor size. for me 16-20Mpx is absolutely enough, but the files of this camera are smaller. And if to shot JPG, the printing will be limited in size. GRii is perfection for me, im staying with it for 7 years and willing to stay forever but these small cameras become problematic after a few years of massive use.
Unfortunate about the durability. I had a GRi that I loved but the lens motor failed and I had to trash it. I think it’s best to use as a secondary camera because they are hard to trust.