[eluser]bretticus[/eluser]
Active Record methods are mostly just setting properties, etc. It's the get() call where the "action" happens. Simply put, it's a database abstraction class. I really don't think it's too heavy. Of course, I've never profiled it against, say, PDO. I'd recommend that doing a simple test would suffice. I think I can guarantee that your bottle neck will be tcp transaction with the database. In my opinion, the benefits outweigh the milliseconds you may save by not using it.