Replacing Dexcool

[MadMaxHSV]

I've read the horror stories so wanted to double check.
Car's been running GM's dexcool to date, but need to replace and the nearest stockist is now a good distance away.
Short of buying a batch online, is there any issue replacing with another red/orange coolant such as Mobil 1 Advanced? Or should the whole system be flushed fully to be safe?

Thanks

[VinceM]

Flush it to be safe but Mobil Antifreeze Advanced will be fine for the Monaro/VXR8.