I say blow your money on whatever type of frame you really want. Your question is subjective and ride quality is based on more than just the frame material.
My carbon fiber-y Domane is way more comfortable than my old Trek 2.3 made out of tooth jarringly stiff hydroformed Aluminum. It also has 32 mm tires running at 70 PSI where the 2.3 has 23 mm tires at 120 PSI. Maybe that is some of the difference.
When my Ti bike is finished maybe it will be the heavenly material that people say it will be. My gut feeling is that it will be fun and hopefully fast and very cool since I am the one who built it ....but at the end of the day its a bicycle.
I'm even thinking about buying a mountain bike and i'm not sure if I really want one that bad ....because ... bicycles LoL !!