I've had the R800 for over three years and have spent a few thousand dollars in consumables. Upgrading my Macs to Mac OS 10.5 Leopard prompted this review. Hopefully some notes here may help others.
Prior to Leopard, getting color balance was quite a chore, resulting in trial and error to set up profiles for quick prints from iPhoto versus output from Photoshop, plus playing around with offsets to get centered prints for 8.5x11. One hint for centering prints was to create actions in photo shop to scale to the exact output size, bypassing the driver scaling and centering.
With Leopard, the drivers seem to have changed. After some problems, I've had success with the latest drivers downloaded from Epson. Follow their troubleshooting tips to make reset the printing subsystem, then reset the "Print CD" utility by (re)starting it, and then connect and set up the printer using the Epson-supplied driver. I no longer have separate profiles for iPhoto versus Photoshop. To print to CD/DVD, make sure to select A4 or A4 manual feed, as there is no longer any hint for CD/DVD page setup.
I had a problem where the printer would not power on (after I had a problem printing a CD, I powered off and extracted the tray and lowered the bed, then the printer would not power on). A hint from the web helped - unplug the power cord and leave the printer off overnight. In the morning, the printer powered on and recovered.
For prints mounted against glass, glossy finish paper sticks to the glass and gives a mottled look. Semi-gloss paper or luster paper eliminates this problem for me.
I like 8.5x11 for inexpensive bulk paper stock and frames. But the R800 can't print 8.5x11 borderless, thus the 9 out of 10 rating. So with the R800, I often print with a wide ~1 inch border for a quick and dirty matted look, it also has the added benefit that the aspect ratio is pushed back toward 3:2, ex., print 6x9 landscape with a title at the bottom in the 8.5x11 space.
About a year ago, I finally bought a refurbished R1800 for $349 from Epson, now I can print borderless up to 13x19. I still us both printers, split between work and home.