...but I did. I picked up a 2015 Giant Defy Composite 1 at a local shop on consignment today.
Ultegra crankset, SRAM Rival shifters, unbelievably light weight compared to my Escape 3. The ride felt great, even on the 23mm tires. Sure, I guess there's some concern about a used carbon bike, but this thing has almost no wear at all that I can see, and the local shop (who has an excellent reputation) doubts there's even 400-500 miles on the bike.
Time to start training for a 50 mile ride I want to do!