Arron,
The early allroads had the single din Concert head unit in them or the double din Symphony. Later cars, I think 2002 onwards had the later Concert 2 or Symphony 2. The Symphony 2 was a 6 disc in dash changer as well as tape player.
Cars up to late 2003 had the RNS-D sat nav system that was CD based and cars from 2004 onwards had the later RNS-E sat nav system that was DVD based.
As mentioned before the bose upgrade involved difference speakers and an amp and didn't involve different head units.
Cheers,
John