If you haven't watched this heartbreaking story yet on YouTube, then you need to. This will give you an indication of why you should clip wings.
YouTube - Tui parrot missing free flying - don't try this
Also, here is another link that will let you know what might happen to your bird if he gets loose accidentally. Believe me, it happens. You think it won't, but so do many, many other heartbroken folks. This bird rescue, which I volunteer for, gets in many pet birds that get loose from their owners. Those found are the lucky ones. Most never make it.
Lost
Please think it through before you decide to clip or not.