Just for the record, I have gathered some informations about models R200, R300 and R800, since I am thinking to buy a model of this “R” series.
About printing engine/quality, it seems that the R200 and R300 models are really the same.
When it comes to the R800, it is a different story.
While the R200/R300 use the standard 6-color pattern (Black, Cyan, Magenta, Yellow, Light Cyan, Light Magenta, aka CcMmYK) with 6 separate cartridges, the R800 uses an 8-color set, more precisely: Photo Black, Matte Black, Cyan, Magenta, Yellow, Blue, Red, and Gloss Optimizer. The last one is a transparent pigment that gives “uniform gloss coverage for prints that look like traditional photo lab prints”, while blue and red inks give an increased color gamut similar to Silver Halide, ideal for sky, sea, sunset and autumnal scenes.
Another difference: the R200 and R300 use a minimum 3 picoliter droplet size, while the R800 has an 1.5 picoliter droplet size.
There are other differences not related to photo quality, like USB2 interface for models R200, R300 and USB2/Firewire for the model R800.
I must say that the R800 is expensive but really appealing…