The 550 was definitely "specialed" Eddie. We have seen a few.
Here's a picture of one (not ours)
[url=http&#58;//i15&#46;photobucket&#46;com/albums/a398/ehj70/oliver/oliver550special&#46;jpg:4vo35eem]550 special[/url:4vo35eem]

I had a feeling that the special may be cheaper version.