I just installed the 3ft. Firestik II No-ground plane antenna. My SWR readings are 1.2 across all 40 channels. It's mounted on my ARB, so it was suggested to go with the No-ground version.
Unless you're mounting your antenna in the center of your roof I would suggest going this route. It's only $1-2 more for the kit.
Here is the company I bought from. A nice guy who is willing to spend time talking to his customers.
http://www.alfenterprises.com/ ------------------
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