Yes the Optical Quantum PHILIPR04 25GB discs due suffer greatly in their quality!!
Out of a 10 disc cakebox, only 2 discs burned properly... the other 8 were coasters! On 3 of the coasters you could see what looked like spots on the recording layer after they were burned. Similar to what a water droplet would look like. That's crappy production standards for sure!
Last time I ever buy that brand again.
I have had ZERO coasters so far with Phillips-branded discs with the Media Code ID of: CMCMAGBA5. All discs have burned with no issues.
So from now on I'll use the Phillips Inkjet printable for my 25GB burns and the excellent Victor - JVC 50GB DL discs from Japan. Media Code ID of: MEI T02 001.