I actually almost bought the ifi xcan, but read about there terrible service and there use of planned obsolescence, it sucks.
It's like we now only get terrible choices. There isn't 1 good strong amp with replaceble batteries.
If you're looking for an amp with replaceable batteries (2x9V) may I suggest Ray Samuels Audio SR71A or XP7. I still use them today and works great with dynamic drivers (Sennheiser 580) and planars (Diana V2). I still have a Fiio Q1 (the flask shaped one) which I got as my first amp into this hobby and battery life is now less than half. It's too bad the battery is not replaceable.