I think not purely because I don't think as many people are 'into' the world of The Simpsons compared with Harry Potter, and therefore the appeal just isn't quite the same. Nonetheless, it will certainly attract enough intrigued visitors for them to make some reasonable profit on it!

With regards to cornering the adult market - does the Wizarding World sell Firewhisky, at all? I would've thought that would be as popular, if not more so, than Duff, with the adult market.

Sounds too much like Duffy the Bear at DISNEY.

My bet is on the Flaming Moe instead. Both Parents and children drinking and toasting together

I think Butterbeer's unique selling point was the fact that no-one could imagine what it might taste like.

It was a mythical creation which had no basis in reality and the fact that Universal had come up with an offering meant everyone wanted to try it, just to see how butterbeer actually tasted.

I remember queuing up for the stuff - bought my souvenir cup. It was massively expensive but, hey, where else in the world could you actually try 'butterbeer?'

For anyone who hasn't tried the stuff its actually like a coke float - very sweet with a creamy topping. Personally it wasn't to my taste. Non alcoholic obviously, though if I had a dollar for every American tourist I heard ask the sellers 'hey is this stuff really beer?'

Doh beer however is a different offering. Most people would expect it to taste of, well .... beer! Apart from the name it doesn't hold any surprises.
There will be guests who want a photo opp holding a bottle of Homer's favourite and I would imagine if its available in take home bottles there will be a big market in souvenirs.
But, bottom line butterbeer will sell more purely because of the novelty factor.

Because anybody under legal drinking age won't be allowed to drink this beer, of course the numbers will be smaller, compared to EVERYBODY being allowed to drink butterbeer. Adults can only drink so much alcohol (or be allowed to)at a theme park, yes? No?