title: spl_autoload_register() performance issues?
body: <p>I guess there's something i'm missing about the pros of <code>spl_autoload_register()</code> over <code>autoload()</code> . 
  From what i read, the advantage of <code>spl_autoload_register()</code> is that it can be registered multiple times, and then when i instantiate a class it will run trough all the registered autoload functions and load the correct one, which will give me more flexibility and allow me to use different functions for loading classes OR libraries.</p>
  
  <p>But how is this considered a best practice to run over multiple registered functions over a single one?</p>
  
  <p>(Or maybe i just didn't understand it at all)</p>