Well thought I would add my $0.02 to this topic.
Firstly I have run across folks in the Porsche concours community that do not wax their cars.
I think in some cases the cars just don't need it. Sure wax adds some depth of color, but judging does not take that into account. Sure wax adds protection, but for the guy who drives the car only 1000 miles a year (to and from shows), is wax protection really needed?
Now don't flame me on this one...just think about it....is the quality of paint so bad, that it will not withstand 1-2 hours driving a month. Add to the issue that some folks don't like waxing because of the risk of wax residue getting in some crack or on some other part of trim. Finally some folks don't like how wax changes the pure look fo the paint.
For me, regardless, I would wax the car. But for sure I will not wax my car any time close to an event. I want to wash the car at least once or twice after waxing to make sure all residue is cleaned up and I have had a chance to look at every inch of the car at least a few times.
The thing that amazes me more than people who don't wax their show cars, are those that wax them the day before an event or even at the event.
