Although I have never personally used this product, I do own an Entrega USB-SCSI adapter and it works well with my CD-RW drive. It looks like Adaptec's adapter works with a variety of devices, so it would appear as if your CD-R is supported. The only other question would be does Toast support your CD-R for the Mac? You can find that out at Roxio's home page. In general, provided you have the correct drivers, a PC SCSI device and a Mac SCSI device are the same... the only difference being the drivers. The dowfall to this is that the maximum sustained transfer rate for these adapters is only about 700 kb/sec... enough for (theoretically) 4x burn speed. Real life, I'm able to burn at 2x quite frequently. Hope this helps.
Cheers!
Chris
[This message has been edited by Chris_G (edited 03-23-2001).]