I, too, am confident the spoiler you are considering will fit your deck lid, but just to be sure, were I you, I'd speak with the guys at College Hills Honda. As you may know, they have a significant online parts business, and I've always found them very helpful when I've called.
As another poster mentioned, you will need new decklid springs and a tool to install them, and they are sold with the spoiler if you buy a Honda OEM spoiler. That's part of the reason Honda spoilers are more expensive than their aftermarket competition, which are often sold without springs to compensate for the additional weight on the decklid.
Oh, and I, too, like the one you're considering. Best of the bunch.