One of my bikes is the Trek 7.3. I like this bike a lot. It is my tool around, take on trips bike.
I think the sale right now is really a great incentive to get one.
I don't know about the Giant but I can tell you that the components on the Trek are a bit higher on the food chain of Shimano.
In my experience it is about fit and comfort. Try both - buy the one that call to you.
Remember that the red Trek is faster, and better than the black one!