Can KindleGen's combo KF8/MOBI files be run on all Kindles?

Hi guys,

I know that the latest KindleGen build makes hybrid files that have both KF8 and MOBI inside them. But does anyone know if these combo KF8/MOBI files can be run on all Kindles?

Kindle Previewer says yes... but I can't check on my Kindle DX because I broke it by accident over the weekend (1 unstable coffee table + one old Kindle DX + one slightly drunk house guest = sad times).

Any help would be great!

Stodder