@Wibbly
You might also want to take a look at
GEAR Software. It looks like they have products that specifically support the RockRidge extensions. The GEAR PRO Mastering Edition and GEAR PRO Linux & UNIX version mention RockRidge support as a feature. Unfortunately, the Mastering Edition is ~$750 and the Linux & UNIX versions, well, require Linux or UNIX. But from poking around on their support page, it looks like the Windows PRO version has some support for the RockRidge extensions. They also have a discussion board, so you can probably inquire as to which version does actually support RockRidge.
BTW, I was sure that
NTI CD Maker supported RockRidge, but so far I can't confirm this.
[Edit 1]You may be able to inquire about NTI CD Maker's features
here. You can also download the trial versions of both NTI's and GEAR's products and see what if any RockRidge support they have.[/Edit 1]
[Edit 2]Does anyone here now if Iomega's HotBurn supports RockRidge? I'd think it would since Iomega bought AsimWare, right? I poked around Iomega's site, but haven't found anything useful.[/Edit 2]
[Edit 3]HotBurn
does in fact have some support for RockRidge. Maybe it's enough for your needs Wibbly?[/Edit 3]