I've been getting the Sense Key = ILLEGAL REQUEST error on all DL disks since updating to 10.6.7. These are Verbatim Disks, have not previously had an issue. In fact I can burn the disks with Burn fine so somehow Toast is boning up. I'm running 10.0.8. I'm thinking 10.0.8 is somehow incompatible with 10.6.7 which is mighty convenient now that they have ANOTHER paid upgrade.
I've begrudgingly paid for almost every upgrade since version 6 but this might be the straw that breaks the camels back. My disk burning needs have become less and less while Toast has become worse and worse, with high priced yearly upgrades on top of it.