Remember Cactus isn't good enough to detect which protecion it is since there are 3 types:
CDS 100 - The famous one with incorrect TOC can be read with most good SCSI models (TEAC,TOSHIBA) and all Plextor drives.
However plextor has a small advantage. What it the CDS-100 protected disc has tracks that fade in and out of each other. For this the only option is the plex I think or it will take much work for a perfect rip ?
CDS 200 - The one whith distorted sound blocks just like safeaudio. This one can be copied with the cdsf.vxd thingie
CDS 300 - Unknown what it does but it should be out there. Rumoured is that this is a test version of cds-300 which will let you rip all.
2nd there are a few other protections
key 2 audio - no problems on the plextor drives from what I have heard.
Mediacloq - The famous protection on Charlie's Prides discs. It is hard but it should be able to copy it with Teac and Plextor drives other drives aren't reported/tested yet.
EAL (CDS-100+ dissimulator) - No drive can rip it correct at this moment but then again this protection is really incorrect. (If you want this one real hard and incompatible then put it on a cdrw. The only thing that actually could play it perfect was my discman made by philips. But then again it has digital out so It still can be ripped
Safeaudio - just like cds-200 use cdfs.vxd
SCMS id - Serial Managing Copy Ship identification . This is a protection which causes problems on most audio cd recorders. But not on the PC ones.
However CDS-100 and EAL do also cause many problems with normal cd players.
The only thing that has been reported to copy most are the plextor drives.