Internet Bandwidth monitoring and policy enforcement

I am looking for a product that can help determine how our WAN is being ustilized and allow policies to be applied to contol bandwidth use/QOS.
The product should allow deep packet inspection so that port 80 etc traffic can be itemized by application.
Can anyone recommend excellent products at a reasonable price point?
Allot Net Enforcer & Websense have been suggested – does anyone have experience with both products and are able to advise?