Well, got Ritek R03 here, and it is beautiful stuff.
Posted a Kprobe scan in the DVD media forum.
I liked Ricohjpnr01, except that it would often hit large PI & P0 errors towards the very end of the DVD, making the file(s) burnt to that section of the DVD cause CRC errors. Also many burns slowly increased in PI/PO errors after burning half way. It is known that Ricohjpnr01 media can be inconsistant.
Ritek R03 is very consistant, P0 average seems smaller than my Ricohjpnr01 scans, PI average seems to be a little higher, but the max PI is lower, on average.
This is based on like 150 Richohjpnr01 burns & scans, about about 20 Ritek R03 burns and scans.
Honestly, I'm happy with 4x, though if I can this quality of burning, at 8x, then w00t!
Note, the new bitsetting firmware, based on that 1.25 HP firmware, still only allows burning to this media at 4x (I was hoping a firmware newer than NEC's 1.06 would support this media at 8x). It you want to bitset this media, does it quite well. I think the burning quality on this media has increased with this hacked firmware.
If you are satisfied at burning at 4x for the moment, this is HIGHLY RECOMMENDED MEDIA, by me