I have the Specialized Allez and ride it multiple times a week between 30-40 miles, avg pace 16-20 mph, do charity rides ranging from 50-150 miles, and do a few centuries a year. So far it has been a solid bike, no quality issues, and gives me enough power when I need it. This bike is pretty cheap (I believe new at $850) and you can find the prior year model at around $600. I don't really have anything negative to say about the bike as a good affordable beginner bike. I've had mine a little over 2 years now and don't see myself replacing it anytime soon.
If you're worried about durability most bike shops offer an extended warranty, just check to make sure the parts you are worried about are covered.