Click on the attachments tab to the left and you can click on the crary and AWS websites. There has been alot of talk on here in the past on which is best but personally I like the looks of the AWS. I think if you're going to buy a new head, then you would want to cancel the standard reel and go with the crary reel. If you are just going to add to your existing head, then it would be better to go with the add on unit. like Nick said, with eleven dollar beans it won't take many acres to pay for it.