A Dynon kit would be half the weight G1000 install, most likely less.
I'm not going to hunt do numbers but an E/AB kitted with a LiOn battery and Dynon setup is easily gonna drop 20-40lbs (mostly battery)
So I agree that you won't increase usable weight significantly, but you are going to reduce weight by a non-marginal amount and also get rid of failure prone parts like vacuum pumps and hoses. Also I can live without the high pitch of attitude indicators.
Just some quick googles of vacuum system weights (in lbs):
attitude: 2.75
DG: 2.7
Turn: 1.5
Vacuum pump: 1.94
Total 8.89
Add in a vacuum gauge, hoses, clamps, mounts, misc and you're at 10lbs.
Gemini concurs:
Compared to a traditional mechanical 6-pack (which typically weighs between 9.0 to 12.0 lbs once you factor in the heavy vacuum pump, vacuum lines, filter, and the weight of the individual instruments), this minimal HDX setup will actually net you a weight savings of around 2 to 5 lbs, while completely eliminating the reliability headache of a vacuum system.
WHen you add in a Lithium battery is makes an even larger impact:
Real-World Impact
To put that into practical GA terms, saving 15 to 25 pounds by doing nothing more than swapping a battery
So your range is 17-30lbs of weight reduction and a vastly superior system.
