Our local Habitat for Humanity tried using a very similar foundation system years ago.
The foundations of habitat houses are typically farmed out to a contractor, but the waterproofing, tile drainage work and back-filling were often volunteer assisted to reduce costs.
In this one instance the contractor was supposed to hold-off on back filling until the first floor platform was in place, and then only bulldoze partway, leaving the fill against the foundation to be done shovel by shovel.
The contractor did not wait for anything (only kicker's holding foundation in place) and bowed in the wall real bad, necessitating an exhaustive dig-out by hand.
Concrete foundations are considered +100 year foundations, wood foundations are considered 50 year foundations, maybe at most 75 years if done correctly. At least these are the numbers I remember from 25 years ago being tossed around.
Here in Michigan we have a lot of clay soil which swells when wet, so I don't like wood foundations at all personally.
http://jbanta.wordpress.com/tag/expansive-soil/
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Regions containing expansive clay soil in this state vary. If you have concerns consult an experienced geologist........
Adapted from the “Swelling Clays Map Of The Conterminous United States” by W.W. Olive, A.F. Chleborad, C.W. Frahme, Julius Schlocker, R.R. Schneider, and R.L Shuster; 1989
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Red Unit contains abundant clay having high swelling potential
Blue Part of unit (generally less than 50%) consists of clay having high swelling potential
Orange Unit contains abundant clay having slight to moderate swelling potential
Green Part of unit (generally less than 50%) consists of clay having slight to moderate swelling potential
Brown Unit contains little or no swelling clay
Yellow Data insufficient to indicate clay content of unit and/or swelling potential of clay (Shown in westernmost states only)
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If you have sandy soil you can get away with murder foundation wise. However there are these things call "veins" which can make you have a really bad day.
To compare soils, this is Michigan.
http://jbanta.wordpress.com/category/state-information/michigan/
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Originally Posted by Paul T
limited research it seems to me that most issues that have been encountered by folks have been due to improper installation and site prep
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True, but remember these flaws are typically learned after the discovery of a problem which could lurk for years undetected.
I'd expect a generous discount on such a home, something to cover a new foundation at least half-way.
You should check with your insurance company too, you don't want higher rates or other hidden costs.