I'm with everyone else- The 730 is a great all around bike. The price is right on with what they go for around here. It is hard to tell from pics, but it looks very clean and in good shape. So, it is not a "steal" but a good everyday price in my locale. At $100 it would be a no brainer. The trailway is ok but not the same quality of the Trek. The giant could be good or bad depending on condition. Fit is the biggest part of the equation for me.
Bruce