I recently purchased a Pioneer 107D from AVlogic and received a Piodata (made by Taiyo Yuden) 8x DVD-R that worked perfectly. I played this disc in both an RCA and Apex DVD player with no problems.
Link to media (there individual disk price is high–$8.00-- try meritline at $3.99):
Here’s another link—judging by the picture it appears to be the same media that I received:
Meritline sells individual disks for $3.99 and 50-500 bulk packs for $3.89-$3.39 per disk.