Thanks everyone for the interesting and helpful comments. I have a V6 FE Emira at my holiday place in Queensland Australia so it is parked in my basement garage for months while I am away. The dealer told me to just disconnect the battery leads - he says they just do that with their cars and have no issues. I did this when I was away for 3 months last year and it worked fine, but fiddly and nerve racking given what I have read about disconnecting batteries on modern cars. However no issues, no warning lights etc.
This trip I just left the car with battery connected. After 6 weeks no use the car fired up immediately which surprised me given my past cars (Cayman GTS4.0, 911 C2S, F88GTB) would not last this long without a battery conditioner.
I'm going to buy a CTEK charger so I've just ordered this magnetic connector which seems similar to the very nice system on the 488GTB:
Making great cars better: Aero•Performance•Parts•Accessories
hethelsport.com
Has anyone had experience with fitting this to an Emira?
Thanks again for all the great advice!