Ray,
You may want to do a little more research on this bike. I've got an '05 S-Works E5, and its a very solid all metal frame. It was sold as a frameset, which leads me to believe its the same one you're looking at (since they're swapping out components). The frame retailed for something like $1200, which makes it seem like gravy to get all new components as well.
If I were you, I'd take a closer look at what you've got in this bike. Are the wheels and components really new, or are they the ones that the prior owner used? If they're used, the deal's not so good anymore: old-stock framesets like this can regularly be found for $500 or so; one that was used for a season of racing and training might be worth less. If you've got a used frame worth about $500 or less, you have to really decide whether a used build group is worth the other $500. It probably is, but something to consider--the answer's in the quality of the components and how used they are. You'll also want to check out whether you'll have warranty on a used frameset; Specialized is pretty good on this, but I think it's the rep's call.
Finally, get a feel for not only whether the frame fits, but whether it'll fit your style of riding. E5's, at least the all metal ones, are pretty stiff. Some people like this, but some find it a hair harsh on long distance rides. Take it out and give it a whirl.
