I recently added the kaenan wing it it looks good, but when my original wing ws off I almost decided to go wingless. I never liked the factory spoiler so I would either go wingless or add the kaenan. I also considered buying a used decklid without holes and going wingless.
I like it with no spoiler but only if you have some big rear wheels/tires. I'm not a fan of the stock spoiler and took mine off a few weeks after buying the car and replaced with a Saleen.
don't like the wingless look on the SN95's, look like they are missing something. But, I don't like our spoilers, either. The SN95 Cobras should have come with a different spoiler from the other Mustangs.