The other day while on a 60 mile ride with 2 friends we stopped at a bike store and i saw a bike i believe was a Specialized Allez/Epic bike. see how cool it looked

i wanted to look them up and possibly get one the Epic bike was $450 and i have no idea what size it was so that could be out of the question. Ive found 2 other Alan bikes one is a 58 ($800) and another is 54 ($1000). i ride a 58 trek 1000 so i think the 54 Alan might be a little too small. I am also concerned about the strength of these older bikes as i have not really been able to find much info. i would hate to be riding down a hill at ~40mph and have the bike brake on me xD.
i would like to know whether or not to get one of the bikes or just get a newer "modern" bike for the same price.
i would be riding around town or the occasional 40+ mile rides or even a century ride that i would like to finally accomplish. im 145lbs 6'2'' thanks in advanced for any info.
the two bikes are all pretty much full dura ace

this is the $1000 with dura ace 7400 parts