I'm 5'-10 and completed a 540 mile group ride last summer at about 220 lbs. I trained really hard for the ride but haven't ridden a lot since. Between the holiday eating and lack of riding I'm currently 235, and can't wait for some warmer weather to get going again. May ride the Oklahoma Freewheel in 2006.
I have an old Trek with all the long tubes carbon, just opposite of modern bikes. If you try to mash it will bounce. They work great as a trainer as it forces you to spin. All the original Ultegra is still functioning perfectly.
The original wheels kept breaking spokes. So I now have Shimano 550's (low spoke count), and they are working fine so far. I just dread the day a spoke does break, probably not riding it in.
My next bike will have a triple crank.
My handlebars are bit higher than normal very much like the new generation of comfort road bikes. I will likely buy a new Trek Pilot (comfort road) or equivalent this spring.
My biggest problem was finding a seat that didn't cause numbness. I tried several "notched" seats and gel seats to no avail, but finally settled on a hornless model from
http://www.tesco-shopping.com/bikeseat.htm . I was also curious about the spiderflex but didn't try it. Hornless seats are not for everyone. When transitioning from standing to sitting you have to find center. It can cause some localized numbness on your "cheeks" after 30-40 miles if you don't stop enough, but this is waaay better than what was going numb. It also took awhile to get my bike adjusted so my hiney hit it correctly and my legs cleared. Now I really like it, but wouldn't rule out switching to a normal seat if I ever find one I can ride. They just look odd on a fast road bike.
I also have a trek cross bike with 700cX28 slick conti's. This is usually pulling my kids in a trailer. A lot of fun but not nearly fast enough.