Personally, my opinion on the matter is this.

If you aren't either A. the fastest subber, or B. The best quality subber, then there is no reason for you to even bother doing it unless you can offer something that other subbers don't.

You know what I'd like to see a subber do? DVD compatible subs. Sure, they will probably be much slower, but if a subber took the time to add the frames and change the file format to something that plays in normal DVD players, I'd download their episodes just for that, so I could watch Naruto on my TV. And even though the files end up alot larger, I'll be burning them to a disc anyway so they won't be hanging around my HD.