I've had beers from both brothers and usually found them to be very enjoyable. I can't say that a beer is good, beer is highly personal, What I like other will not. I live in a state with an obscene number of breweries a large number of the well lauded ones I find horrible (Oregon is obsessed with huge hoppy beers which just aren't to my taste).
I usually prefer a Mikkel to an Evil Twin.
I'd rather be drinking Stillwater or better yet Fantome if it's a Belgium style beer. If you ever see a bottle of Fantome under $30 just buy it, I think the guys beers are special. Look for a cartoony ghost on the bottle. Stillwater is way easier to find and while I haven't liked everything I've had from him he's made some of my favorite beers (it's cheaper than Fantome as well).
The two brothers story, while interesting, doesn't really make me care more about their beer one way or the other. Both guys make beers worth checking out.