This article:
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might provide some valuable insight into the mechanics behind breeding of luxocoaches. Looks like there is no shortage publications who like to brainwash American public into buying Heavy Pigs Unlimited.
Got something that protects from a side impact by a train doing 45 mph? How about a runaway semi? Rocks hitting you on the head while going in a convertible with a top down in the mountains? No? How about losing traction in a slick turn because the tires were not quite up to the task of keeping
3000 pounds on the road? There are some very interesting abysses in Sierras.