I bought a Felt Z series bike and my husband bought a Giant Defy Advanced series bike. Both of them are considered 'comfort road bikes'. They say 'compact geometry' or 'endurance geometry'. Both look like full road bikes, not wanna be's. My husband never tried a standard road bike geometry, but I did. The main difference I saw was that I was not all crunched up into a pretzel with the Z series. I am still bent over a good amount when my hands are on the hoods and very bent over in the drops, but if I want to I can put my hands on the cross bar and be sitting up (I use the term loosely).
Here is what they say about the Defy Advanced:
"At the heart of this aero-sculpted beauty is an Advanced-grade composite frame with endurance geometry for increased control and comfort. Performance features, like the PowerCore bottom bracket for optimal pedaling stiffness, are blended with a road-smoothing, longer wheelbase and taller headtube. It’s the best of both worlds."
Here is what they say about the Felt Z series (they like to yammer on):
"Whether you’re racing or attempting to complete an all-day epic, comfort is a critical factor in your performance. It’s simple: The more comfortable you are, the better you’re able to ride. That’s where the Z Series comes in. It’s specifically designed to blend performance and comfort so you can ride farther and faster—and enjoy every ride more than ever before. Take a look at some of the bikes used by pros at long, grueling races like the Tour de France over the years and you’ll notice they were a bit different than those that are popular today. They were built to be stable on fast descents and featured a slightly more upright rider position. They had longer wheelbases and offered excellent vibration damping—proven ways to reduce fatigue. These ride characteristics are central to the design goals of the Z. Z Series frames use a slightly longer head tube for more flexibility in handlebar and rider positioning. They feature a sloping top tube for increased stand-over clearance, and they benefit from improved vertical compliance due to a more exposed seatpost. The Z also features a slightly longer wheelbase for confident handling at any speed. Even with those modifications, the Z still packs the same torsional stiffness and bottom bracket rigidity as Felt’s legendary F bikes. It all adds up to a bike that can be ridden in classic racing position, yet also provides options. Even with its distinctly different look and eye toward improved comfort, it’s a mistake to think of the Z as a non-performance-oriented bike. Many of Felt’s pros choose the Z for select races.
Whether you choose a Z model built from super-premium UHC Ultimate+Nano carbon fiber and cutting-edge electronic Shimano Di2 shifting, or one of the lightweight aluminum/carbon fiber models, you’ll get the same assured handling and race-worthy stiffness. It’s a ride that’s as responsive as it is confidence-inspiring. All Z Series bikes are built with the right components for the ideal fit, plus gearing for any terrain and unmatched reliability. Each bike is equipped with either a compact or triple crankset combined with a wide-range cassette to help you tackle hills. If ever there was a bike to inspire you to reach new heights, the Z is it."
We both wanted endurance over speed in a bike. Both of our bikes are capable of going much faster than we care to go, but at the same time I have been able to ride much further than I ever could on my old bike.
