I almost always opt for subs. I just find it more enjoyable to listen to the original Japanese VAs. Plus the vast majority of the anime I've watched don't have dubbed versions anyway.
I always read and am constantly told that Cowboy Beebop is a great example of dubbing done well, but by the time I've finished whatever series I was on I've forgotten that I meant to watch it and end up moving on to something else.
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