I would say the 1.7 times larger is about right. I have both Rouens and White Golden Hybrids from Metzer Farms. The WGH's give me an egg a day and have been for about 3 months now. The Rouens have been laying for about 2 months and one has been hit or miss.
I have converted a few folks to duck eggs since they have a richer flaver and larger yolk. The fans who like fried eggs will become loyal converts. And as stated earlier makes for richer baked goods.
The biggest problem is wanting to eat more because they taste so good.
Mond you, I have both ducks and chickes so I compare the flavers and qualities side by side regularly.
My ducks (the runners) have just started laying. Right now I'm getting 3 eggs a day.. We eat them as we would chicken eggs, and I'm happy to have fresh duck eggs to use for baking... Don't have turkeys YET....
No turkey eggs yet for me this year, still waiting for my hen to start, but usually I do not eat them, every egg I get goes in the bator or under a broody hen.
I do not like the taste of the turkey eggs, their eggs are udderly tasteless. I can always tell when mom makes scrambled eggs out of a turkey egg, it just tastes so ...........
Also I get really sick from eating turkey eggs, dunno why, I can eat like 3-4 duck eggs without a problem, after half a turkey egg I am ready to throw up.
Duck eggs are the way to go if you want a nice tasty egg, same with guinea eggs, yummy.