It looks like this thread died. But I thought I would throw in some info I have gleaned from raising a couple of feeders. First, don't believe the folks who tell you that you can raise a pig to slaughter on 250 square feet. You'll have a stinking mess unless you love to shovel. I have a quarter acre fenced off with welded wire and a strand of electric fence inside at about 8" off the ground. They quickly learn to back up if the fence is there. They are not so quick to learn without the fence. However, if you train them from the time they are born to be used to backing away from the electric wire rather than going through it (i.e. if there is a fence beyond the electric wire), you will not need a strong fence. They will see the yellow standoffs and avoid the fence most of the time and will hit "reverse" when they do accidentally run into it.
My recommendation is to start the small piggies (weaned usually at 10-15 lbs) in an area with an electric fence and a welded wire fence beyond that. If you want to, you can then move it to a larger area with an electric fence only. Be sure to provide shelter from the rain, dry bedding, and your feeder. Some people here on BYC ferment their feed for their chicks. Your pigs will also love fermented feed. It will help their digestive system (which on a pig needs all the help it can get), the swine seem to like it better, and they seem to eat less feed per pound of weight gain. I have not charted that last bit, though, so it could be just me.