Maybe it's just me but the Cowboy Bebop dub didn't seem as fantastic as most everyone says.
And yes, I listened to five seconds of English Alucard speaking, mentally puked, and never came back.
Only dub I watched extensively before was the Tenchi OVA one. They get the mood and "tones" right, but Ryoko's voice doesn't compare to the Japanese one; same for Ayeka. I think Washu, Kagato, and Mihoshi's voices fit pretty well though.