Not sure about the '1x Motion, even when the system is disarmed' feature. Do you mean as an aggregate of any motion detector in the system ? If so, this would probably need to be done in software.
The G2 is a solid panel, but doesn't really hit the spot when it comes to home automation. It has a limited set of output options / links. The Flex is okay, but I would still opt for a Dimension 48 which has a nice big metal case for extra boards and a big reliable wirewound transformer.