Before i watch the anime, i check both subs and dubs. If i don´t like the dub, I go for subs. If i like the dub, I go for the dub.
I have only watched three dubbed animes:
Death Note (both English and Czech, though the latter is very hit or miss imho. Either the character sounds fine, or really horrible. Nothing inbetween) (and yes, the czechs dubbed quite a lot of anime, until Animax stopped broadcasting here in 201X, don´t remember the exact year) (not posting a link (" no unlicensed downloads and streaming sites")
Jojo´s (The english dub is good, no one will change my mind.)
Hellsing (Also dubbed in Czech, czech Alucard is fantastic as far as czech anime dubs go.) (not posting a link (you know the deal)
EDIT: as it turns out, both czech dubs are on youtube lol (still not posting the links because i am unsure if the rules cover that)