Dear Moosa
the update of the gold image will not effect ur machines specially it will not effect ur vdis
but im still woundering why do u want to update ur vdi's while u can do it in the traditional way
it will be much safer for u and it will not effect u
further more u can make a trail run by doind a small test
create a new gold image and from that image create vdi's then update that new gold image
and see if it eill effect ur new machines in the MAC addrrss as u was worried
Regards
Osama Omran
ps are u at oman because in in oman too