The most important thing is to make sure it fits. There's only so much that can be done by changing bars / stem & seat. The second most important thing is do you feel comfortable on the bike? Does it ride too stiffly? Does it handle, accelerate, brake & corner all right? Look closely at the wheels. Decent wheels are expensive to buy. Wheels need to be light, yet sturdy. A nice component group is a major plus. Included in this is the ders., front & rear, maybe hubs, crank, headset. Look for Shimano 105, Ultrega or Dura-Ace. If it's Campy look for Chorus or Record.
I strongly suggest that you take a knowledgeble roadie, (if you know one), to look at the bike with you. Specialized is a good name brand.
You're probably going to find Shimano Sora road bike components on an Allez for $475. Sora's shimano's entry level, but it's not bad. If you want to race, yous hould probably consider upgrading it at that point, or getting a higher end road bike to start with. Usually Shimano 105 is considered raceworthy. Sora's a bit heavier, bit slower, bit more finicky, in my limited experience with it.
A forum community dedicated to Road Bike owners and enthusiasts. Come join the discussion about bike parts, components, deals, performance, modifications, classifieds, troubleshooting, maintenance, and more!