BTW folks, heard word from Tech21 on 'that other forum' that the XLR 'is darker' than the main output, as per Dug's specs. Whether this means there is no speaker sim at all on the main out, or just a brighter one, remains to be seen!
Just for those folk sending the XLR to the desk and the main out to your FRFR wotsits, you won't get exactly the same tone out of each.