This is an interesting combination of two Rhone whites. Marsanne is the grape used for white Hermitage; Viognier is the only grape allowed for the Northern Rhone appellation of Condrieu. The Australian d'Arenberg winery blends them at 76% Viognier and 24% Marsanne, and it works well for me.
The color is deep yellow, as you might expect from even a young Marsanne. And on the first night I get a lot of Marsanne character. "Glue" is sometimes used as a descriptor, and I smell glue here. That may sound negative, but it really isn't when you smell it in a wine. It's a broad earthy smell that might match up well with a crab bisque soup. Concentrated and deep.
On the second night, the Viognier peeps out with a completely different personality--white peaches, spring flowers, crisp acidity to counter the Marsanne earth. Viognier is generally not considered a wine for aging; Marsanne seems to improve even over several decades. For this wine, I would be tempted to let it age for awhile, knowing full well that the color might get deeper and less pleasing to some.