do those high power lighter work? they suppose to produce high heat flame that is wind proof.

They do, but so do the cheap and plentiful bics, as well as common, ordinary matches. When building a fire, you will not be lighting and maintaining one out in an open windy spot. Somehow, someway you must find or construct a sheltered microenvironment for your fire if it is to be effective. In that situation, any of the common and cheap ignition methods will work quite well, or at least well enough.

My Hi dollar (gift) lighter does not work at med. and hi altitude.
Above 6,000 feet I do not trust it, at 8k it would not work.

I expect it is the temperature that is the issue. Higher altitudes have less air pressure which would increase the pressure differential from inside the lighter to outside causing the vapor to exit faster. However, butane will remain a liquid when cold and thus not build any pressure inside the lighter. Of course, it is generally colder at higher altitudes.

Butane boils at 31.1F, so if it is colder it won't exit the lighter.

With lighters you can simply warm them by carrying them in an inside pocket.

I'm carrying the butane soldering iron when car camping and in my urban GHB. It has quite large gas tank compared to the bic or other torch lighters for smokers, the reliable spark wheel ignition, wide range of pressure control, and several interchangeable tips for different work - very versatile. The high temp torch flame helps to ignite almost anything without much preparation i.e. in a hurry. It will dry wet kindling almost instantly, ignite raw BBQ charcoal in several seconds, e.t.c. And of course you can solder some electrical wires or metal parts if the need arises (with a piece of rosin core). And it is the size and shape of a large marker - easier for reaching kindling's center in a pile, compared to bic and others. I like it very much.

^ That butane soldering iron is a good idea. I have my Bics and Sparklites and a "butane blowtorch"-type lighter in various places, on me or in my bag/car. It's funny you mentioned it, because I was just thinking about electrical things possibly breaking outdoors, or maybe some jury-rigging needed, now that I tend to carry more small electronic gadgets.

You reminded me that I have an "ancient" Weller Pyropen Jr. (quite decent actually...) in my toolchest that's not doing much these days. Completely forgot about it even though I was specifically thinking of field repair, that's not good , it's light enough and may have other uses (the blowtorch mode). Edit: not a fire-starter, you need a lighter etc. to ignite it.

I have this one
http://www.napaonline.com/Catalog/CatalogItemDetail.aspx?R=PHI4054_0218262119

I have successfully used the trustworthy BIC brand lighters above 6000' with no problems in both summer and winter. In cold weather, no matter the elevation, BIC lighters should be kept in an inner coat pocket and they will then work without problem well enough to get your fire or stove going.