[CSSer]

This can vary a ton as well. I was talking to a friend yesterday who said he was pounding a native browser interface with an iterator and experiencing slow performance. He switched to buffering the entire thing into memory first and experienced huge performance gains.

The aspect of the language you're using, if optimized, is virtually always optimized for the most common use-case. If your use-case isn't the most common use-case, you must account for this.