[CrimsonNataku]

Your decision to watch an anime in its dubbed form or subtitled form makes no difference when it comes to who is a "truer" anime fan. Personally, I think so long as you aren't so biased that you aren't open to trying to watch an anime in dubbed/subtitled form, then it doesn't matter.

There are good dubs, and there are bad ones. By the same token, there are good and bad subs too. I have seen TERRIBLE translation jobs. Some of them were fansubs, but others weren't. In fact, there was one anime where, when compared line by line, the DUB was closer to the truth than the subtitles.

Example
Dialogue spoken: Kuso!
Subtitle: No!
Dub: Damn!

It's all a matter of opinion and personal preference.