Would a Vanilla Porter generally be served on Nitro or CO2?
Not sure but it sounds tasty on nitro.
All I know is that Denny’s Imperial Vanilla Bourbon Porter is pretty tasty on Nitro
I’ve always noticed that Nitro does scrub flavor and aroma out of my beers, so I alway put fairly strong flavored beers on beer gas.
This is why dry irish stouts taste so good with sooo much roasted barley in the grist.
Personally, I hate nitro beers. Knocks the carbonation out and makes the beer seem flat and lifeless to me.
No harm in trying both. Start with low carbination on Nitro. Then you can alway bring up the level afterwards and serve with CO2 and see the change. Some beers I have tried on Nitrogen imediately cried out for higher level of conditioning. Some were way better on Nitro.
Conditioning definately effects the character of the beer.
High CO2 accentuates hops and bitterness / covers malt and sweetness.
Low CO2 - the reverse.
As for other characteristics including off-flavours, diferent conditioning brings out or covers up diferent things.
Porter is a beer that could go either way, but I don’t usually see them on Nitrogen (no reason why they can’t be though)