Jim,
I am currently trying to finish up my first home that I have built acting as the GC. It definitely has its advantages and disadvantages. It is my opinion that the advantages easily outweigh the disadvantages.
Things to consider: To do the 'GC' job right, you need to be on the jobsite on a regular basis. This meant, for me, taking time off work to be at the house during critical stages of construction. Sub-contractors can make or break you, not only financially, but with quality of work and scheduling. My experience has been that for the most part they do the work quickly, but often at the sacrifice of quality. So if you want quality work done everywhere, not just what you can see, you need to be present to oversee your subs. If you are fortunate you can find quality subs that you can trust which takes a big load off of your shoulders as far as trying to oversee all the details. Unfortunately, they are hard to find. Also, just because a sub bids a higher price does not guaranty higher quality.
(Soapbox in place) My biggest complaint about soceity today is the lack of pride in workmanship. It does not take much longer to nail a board straight than it does to nail it crooked. If a craftsman gets in the habit of doing good work, he can do it just as quickly as someone doing shotty work and probably not have to go back and correct mistakes. The other things you see is the 'pass the buck' mentality in the sense that the framer says, well this will be covered by drywallers, the drywallers say this will be covered by the tape/bed, tape/bed guys say, the painter will handle that, etc. Anyway... (off soapbox)
Out of all the subs I have used so far, which includes, concrete, plumber, framer, roofer, electrician, drywaller, tape/bed/texture sub, trim carpenter, painter, siding sub, and brick layer, I would only highly recommend the roofer, siding guy, and the brick layer. I would probably use the concrete, plumber, drywaller, tape/bed/texture and trim carpenters again because there costs were low enough that the areas they were less than perfect in were very few and not real critical. Probably would not use the same framer, and definitely use another painter.
Just FYI, the framer only did the roof construction and set my windows and exterior doors. My dad and I framed the first and second floors up to the top plate. We, of course, were very meticulous but slow. I hired the framer to finish out the framing, and he did it quick enough but his use of material was very inefficient and I had to order more lumber than was originally planned and his crew was not quality conscious at all. This was all very frustrating beacause of the type work we did on the lower part of the house.
Overall, though I have learned a lot and would not hesitate to do it again, besides, lesson learned would make for a smoother process the next time around. The amount of savings and value that you have built in is almost staggering. I estimate I will have 100k dollars of sweat equity built in not to mention other money put down from selling my current home.
So I would recommend it, just go in with your eyes open, expect some things not to go so smoothly, expect to spend a lot of time on the jobsite, get some tractor time, and enjoy the fruit of your accomplishments. Inserts cliches here: 'Nothing ventured, nothing gained!', 'No pain, no gain!', 'If it was easy everyone would do it, be different!' /w3tcompact/icons/smile.gif
P.S. My house is 5 bdrm, 3 bth, 2 car garage, two story, 10 ft. and a few 9 ft. ceilings, 3550 sq. ft under roof, about 3050 living sq. ft. If you can, build a little samller the first time around, build 8 ft. ceilings it will make you task much more bareable. I have 5 kids and needed the extra room. /w3tcompact/icons/wink.gif
Hope that helps!