I would suggest the opposite.
Keep the Octopus, ditch the Air2. Especially if you are diving locally (British Isles). If anything, the suggestion would be to get a longer hose on the Octopus.
If you need an AAS the stress will be high, (both for you and your buddy,) so the best performing regulator you can get.
If you use an Air2, then you will have to swap from your primary reg to the Air2, and then donate your primary reg. Whilst primary donate is done at tech level, you are not at this level. There is a higher risk of two casualties rather than one. If your buddy attempts to use the air2 they will be right in your face, not a nice place to have a potentially panicking buddy.
The Air2 will restrict your head movement, in an emergency this is not ideal.
Either way someone is breathing from the air 2 - probably you - and you will be attempting to control your buoyancy with it at the same time - not good.
Visibility is vary variable in the British Isles, from truly fantastic to not being able to see your hand in front of your face. The AIr2 doesn't suit poor visibility diving.
The Air2 is also more likely to confuse your buddy. An unfamiliar diver will often press the purge rather than the dump. Not ideal if they are lifting you and trying to control your ascent rate.
Gareth