Buzzbomber,
The Delta 20 newfie put up is a good illustration of a double similar to the G3 Passat in many ways, two feet shorter in length overall, very close in beam, but with much more volume in the ends. However, though dry storage aft is about the same as with the G3, the 20T is smaller in the forward storage compartment by about 20 L. It looks like it has about the same length at the waterline, which is important,, because a longer waterline makes the boat faster. However, this boat will likely be a little slower than the G3 because of its fuller ends. On the up side, more volume in the bow makes for a drier ride for the bow paddler. A knife edged bow such as that in the G3, will slice into waves, perhaps enough to send water on to the bow paddler when conditions are rough. Becky finds that very annoying in our CD Libra, but it does not bother me, because I am behind her. She makes a great shield against wavesplash!
She is throwing things at me as I type this ... ouch!
It would be worth comparing the total dry storage of these two boats to see which one has more. It would be good to paddle this one and fhen the G3 to see how much difference there is in speed.
Unfortunately, Delta does not show how the center dry storage is bulkheaded, so that is something else to look at when comparing the two boats. Delta makes no claims about efficient, curved bulkheads, so I am guessing the use of space at the center is not as good as the G3.
I suspect, at 26.5 inches beam versus 26 inches for the G3, and a similar length at the waterline, this may be nearly as fast as the G3, and as good a boat for a week long trip. Perhaps you would need to deck load, as with the G3.
All this analysis of the two boats from specifications and hull shape means little compared to what you experience when you test paddle the two. I will be curious what you find out if you do paddle both. Have fun with it. You can learn a lot from test paddling, finding out how the hull works for you, in lieu of relying on the opinions of others.