As has been said, the panels are completely duplicated (backlight & inverters) etc. I am actually and electrical engineer and whilst it appears the design is very well duplicated one thing that often isnt is the software - i.e. a bug will appear in both screens - but is very unlikely. As it happens unlike the avidyne the G1000 will reboot in the "air". The avidyne must be on the ground!
I have actually tested this in flight (dont ask..)
I have also suffered an AHRS failure - very worrying! But in reality with all the rest of the nav stuff it not that difficult. From years of steering boats with mag compasses in very bad weather a plane was easy - BUT without a GPS or VOR etc. I would feel very uncomfortable and certainly get radar or DND assist.
I did hear of a fellow where the fans died (and he didnt notice) and the panels overheated - so it is possible - but very difficult.
I had a similar conversation with my wife years ago (about boats) - and after an repeated number of "what if's" I came to the conclusion that eventually you are f....ked - so enjoy your life while you can! You can only protect against a given number of simultaneous failures, and then you have to wing it...
What I am certain of is that compared to the convetional (non-duplicated) instrument panel I would go for the glass every time!