diamond kote rust-proofing for car worth it?

[Greenblatt]

We are buying a new car (Subaru) and the dealership suggested a diamond kote rust-proofing. The lady showed us some kind of wax and plastic that are put under the car and in the side panels. I asked for more information but she only gave us a brochure with a grand total of 6 lines on the product. The product is said to offer a 10 years protection. The plastic stuff under the car (vulcanized rubber?) is also supposed to offer sound protection.

I had never heard of this product before and was initially just thinking of doing the annual anti-rust oil thing (about 80$/year). Technically Diamond kote would be cheaper (600$/10 years). At this point effectiveness and quality are more of a concern than the price.

We live in Canada and the car would be new so anti-rusting is a necessity. Do you know this Diamond Kote product? Is it good?

thank you!

[theglidd]

Most cars come with a standard rust perforation limited warranty. Usually it's 5 to 10 years. Check what Subaru provides.

I doubt you need anymore protection than that.

[CmFtns]

Never ever buy up sells at the end of the car buying process... most of what they offer is definitely not needed and ANYthing they offer can be found aftermarket or other superior products can be found aftermarket often for much cheaper. Do you research and find the best product yourself instead of trusting the dealership saleman who get's as much money from selling undercoatings and plastic wraps as they do for car sales

I've got a subaru in coastal florida and there's not a hint of rust anywhere except the brake rotors but every single car has that down here

EDIT* Found this on a different board explains it pretty perfectly
http://boards.straightdope.com/sdmb/showpost.php?p=10972305&postcount=10

[Reynolds531]

My cars have always done very well on oil spray here in Ontario. I doubt the tar/undercoat gets into seams etc.

[alsoknownasDean]

If it was that important for the car, they'd put it on at the factory.

[h82goslw]

We'll keep it simple.....DON'T BUY IT!  Waste of money.

[paddedhat]

If it was that important for the car, they'd put it on at the factory.

LOL, the OP is discussing a part of the world where the roads are coated with a sloppy mess of ice control agents (rock salt, chloride slurries, etc) for months. I have seen five-ten years old vehicles in those conditions where the leading edge of the hood was simply missing. The salt just chewed it off. Other similar vehicles with giant holes in rocker panels, and rot through the fender lips. Cars taken out of service because suspension mounting points on the unibody simply rotted off.

 Here in the snowy/icy parts of North America we went from cars that were junk and would rot out if parked next to a bag of salt, to cars that were pretty well built and durable. This lasted until a decade or two back, when litigators and various municipal agencies decided that all roads should be completely drivable, regardless of how ugly the weather was. So now we "pre-treat" roads with stunningly aggressive salty brine solutions, before and if a storm is predicted, and we salt the living shit out of everything. The damage to the environment and vehicles is staggering, but hey, at least the local soccer moms can get their little monsters dropped off at their play dates, without be inconvenienced, and they can drive their all wheel drive SUVs at highway speeds, regardless of conditions 24/7.