I like the idea of a long lasting roof but seriously does it warrant four times the price of ashphalt shingles?  Afterall, I'm not going to have to replace my ashphalt roof four times, maybe twice would be realistic. I would figure that a metal roof should be less expensive considering its just made of metal, not gold plated, and produced in a factory. Also, metal roofs were traditionslly reserved for low cost projects like barns. So are we just getting ripped off because metal roofs have somehow become an object of desire?

I don't know where you live. But in our climate, the basic three tab (asphalt) shingles that are warrantied for 20 years, will last about 8-10 years. A dimensional shingle with 30 year warranty might last 20, if you are lucky. And that's assuming no major hail or wind damage. About 12 years ago, I installed a bright red metal roof on a home we were building. Three weeks later, a major hail storm hit our community and destroyed over 50% of the roofs. The metal roof had no damage, none. Today, it looks just as it did when it was installed. And some of the shingled roofs replaced after the hail storm have already been replaced, again.
Yes, metal is more expensive, it always has been. But it was worth the difference years ago, and it still is today.

Personally, I would like a metal roof for all the reasons you give. I live near Montreal by the way. But why does it cost four times as much as ashphalt shingles? I just wonder how much is down to production costs and how much is mark up for what is perceived as a premium product.

they arent worth 4 times the cost. i really only see them worth the cost in high snowload
areas like in the mountians because snow will slide off them easier and they are good in fire areas.
i live in south dakota and
i assure you that they will dent in hail storms. maybe our hail is harder here.

There's a wide variety of cost in metal roofing.  A true standing-seam metal roof will generally be the most expensive and simple corrugated roofing (like your barn) will be the least.  There are several steps in between - concealed-fastener panel (that looks very similar to standing-seam), AP, R & U panel if you're looking at Mueller's products.

The complexity of your roof will have a big impact on installation costs.  A simple rectangle with 2 gable ends will be much less expensive than a roof complicated by cuts, dormers varying pitches etc.  Keeping it simple keeps the cost down.

In addition to appearance and durability, another factor to consider if you're in a sunny climate requiring air-conditioning, is energy costs.  A light-colored steel roof is highly reflective - significantly reducing the radiant heat gain through your roof. 

No, I'm not in the roofing business I just like 'em.

richwood,
I suspect it is some of both, especially if you are talking to residential roofing contractors who work mostly high end projects. You might check with commerical or agricultural suppliers for other options.

vhehn,
if your roof structure is prepared correctly, a metal roof will survive under conditions that would destroy a shingled roof.
a few dents vs. a total roof replacement is a very good tradeoff, I think. The hail may be harder in s. dakota, or the roofs may be built differently, I don't know.