I picked this off an e-mail I got from a car detailing company. It's a good summary of the advantages and disadvantages of the 2 types of car wax. For me I go with the longer lasting Polymer waxes.

Carnauba Waxes:

Advantages:

A darker, deeper, richer shine.
Best carnauba waxes produce a liquid, "wet-looking" surface.
Carnauba waxes tend to hide minor swirls.
Carnauba waxes bead water (tells user when to re-wax surface).

Disadvantages:

Limited durability (Carnauba starts to melt at 180 degrees F).
50% gone in 30 days, 75% gone in 60 days, re-wax in 90 days.
Some carnauba waxes are harder to apply. (Require more effort to buff off).
Some carnauba waxes create chalky- white residues and stain trim moldings.
Low surface adhesion - can be removed by car washes and detergents.
More prone to water spots.
Usually requires a strong petroleum solvent base.
Can cloud and/or streak on dark color cars.
Can be difficult to apply by machine.

Polymer Paint Sealants:

Advantages:

Longer lasting. (Most will last six months or longer)
Easy to apply.
Very bright shine.
Most sheet water which reduces water spots.
Stronger surface adhesion resists detergents.
Usually easy to apply by machine.
Can be water-based or use a mild mineral spirit.

Disadvantages:

Bright shine is often referred to as sterile, lacking emotion.
(it does not allow the paints true pigment to show through)
Tends to highlight or amplify minor swirls and paint imperfections.
Sheeting does not give a visual clue of when to recoat.
Some products have long cure times between coats.

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2006 VIN #30, first 1000 series, black exterior, sand/steel interior
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