It sounds as if the Defy 2 Composite has called your name, but I'm putting my vote in for trying other bikes before you buy. I really like Giant bikes and I have a Defy 2 that fits me like a glove. I really love riding that bike and if the frame were carbon fiber, it would still be my only road bike. Good luck with your search and purchase.
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HCFR Cycling Team
Ride Safe ... Ride Hard ... Ride Daily
2017 Colnago C-RS
2012 Colnago Ace
2010 Giant Cypress