Buy what you like and can afford. You may need to do a bit more riding, but to me it sounds like you have found a bike that you like already (the Giant). Do you plan on racing? From what I understand the Giant TCR bikes are set up for racing. You may be able to find something for quite a bit less money that will give you just as good a ride. I really can't recommend any for you, you just need to ride them and find what sings to you. I can say that I test rode more than 4 bikes before I made my purchase. I ended up with a LeMond.

Cheers,

Brian