Hi, not done this yet but it will happen this year. There's no different
device class for AIT2 so in theory you could just replace all your drives
with AIT2 and run with the old AIT1 media.

You will not get all the performance and capacity benefits though. According
to a Sony engineer you will get about 4mb/s native from an AIT2 drive with
AIT1 media as opposed to the 6mb/s with AIT2 media.

If you get any more help or experiences please share with the list as this
is something a number of folk are going to face, AIT has been quite popular
with *SM. Likewise if we do it first I'll share it.