But if you import the Satoshi wallet.dat file, you still have the "dead weight" of all those keys in you Armory wallet, i.e. you miss the simple backups (since all the old keys need to be backed up separately, whereas all the Armory keys are backed up together, as they are generated from only two huge numbers).

So if you want the full power of Armory, you should not import your Satoshi wallet.  You should create a new one, and transferring the funds by sending them to an address in the new wallet.