I do the same but even then sometimes I already dislike the English cast on it's on merits not having even seen the Japanese. Then I switch to Japanese because it's just more pleasant on the ears. Such was the case with Zeta Gundam (it's a Blue Water dub, they almost always suck), Hunter x Hunter (same, another Blue Water dub), Girls Bravo (a surprisingly bad LA dub coming from New Generation Pictures that has plenty of talented folks but they're acting is pretty bad).