It will make a very good backup device and you can use your 70VG juice in there, no problem. You also get a few coil options for the AIO.
Just remember that the AIO is a more mouth to lung device.
I was using the 0.5 coil that came with the Gemini and had a dry hit here and there and occasional leaking. Had to do the top cap trick to release bubbles, etc.
I bought a 0.9 ohm ccell coil today and man, what a difference. Unpacked the coil, primed it and pulled a few times without firing...