Yeah check out the land first like Jeffmo said. My sister and brother in law had a "The Adams" built on thier own property way out in the boonies. It has been about 2 years so far and no problems yet. I recall a few little instances during the build that my sister was a little stressed over, but all in all I have seen people get more stressed over a cookie cutter Dominion Home build so it couldn't of been too bad.
To save money my sister and brother in law decided to paint the walls and stain the trim themselves. Painting was no big deal we all pitched in, but if you plan on staining your own trimwork, please think twice about it. That is one job that is better left to the professionals to do, lots of sanding to get it right.
During the build process I found out another co-worker had close friend that had the same house built a couple of years previous, and according to him they love it so far. Those are the only two people I have heard of building a home with American Heritage, and both seem to like them just fine, haven't really heard anything negative about them yet. I am not to sure about them being to negotiable, I didn't hear about that aspect of the process, I know you can do some of the work yourself and cut the cost back.