So how much would it cost to have the whole car resprayed with a hard clear coat? And would it look ok?

I had a clear bra installed on my car immediately after picking it up from the dealership. I was never a fan of how they look, but it is worth it. I only have one small chip in the middle of the roof and that's it. 3300 miles and a 8hr road trip later. Swirling and such can be controlled like others have said with proper washing techniques. Invest in a Porter cable dual action buffer and you can keep the scratches and such under control .

A tip! On the freeway travelling at 100km/h you should drive approx 50 metres or so back from the front car to minimise chips.

For us in the US that is about 60 MPH. :D

I do not know the name of the devise. But there is an instrument that is used, to measure the thickness of paint on cars. Out of curiosity! I would like to know/ compare the thickness of the 370 paint, compared to other cars*!

*except the GTR, I believe it has multiple coats of clear coat & paint!

It's called a PTG (Paint Thickness Guage).

Here is a great one for not too much money!

Paint Meter, Paint Gauge, Paint Gage - HighLineMeter.com

How do you wash/wax the car with the sections of clear bra on it? Do you even wax the section?

You can correct a clear bra with machine polishing, you just can't use too much heat or be too aggressive.

Like already mentioned it's a paint thickness gauge. I've owned one for many years and measure every paint job I work on. The Z is 4.5-5 mills thick. This is an average thickness, and I also find, for my car, it's an average hardness. But, I would like to mention that from my personal experience, no two paint jobs are alike in hardness even for the same model of car. Here is an example; I polished two 2006 BMW 545i's. One black and one silver. The black colored BMW had very soft paint where the silver one had rock hard paint :confused:. Neither one was a repaint, as they were new, and they measured the same thickness, give or take a fraction of a mill. I see this all the time. So some of us are bound to have soft clear coats while others, like myself, will have harder clear coats. It's just the nature of the paint process. This is not a new topic, we have discussed this on the Autopia detailing site for years to no avail. All I can say is, if your one of the unlucky ones with a soft paint job, you better invest in a clear bra and a "PROPER" wash program. Good luck.

You should regularly seal the clear bra with a polymer sealant. Polymer based products are generally better than wax for plastic. Be very carful if you polish the clear bra. I'm not saying you can't polish it, it just very delicate and you need to use a very mild abrasive with a mild process. That means a soft pad on low speed with a mild polish. Rotary polishers are not recommended.