105 level not that much more expensive and well worth it.

With your experience I would imagine that you can maintain and perform at least minor repairs on a bike. You can get a lot more bike from Nashbar or Bikes Direct than a "company name painted on probably a Giant frame anyway" store. You can probably get a few levels higher in components for the same money. There's threads to search for on the topic. As many opinions favor as oppose. One of the latest positive reviewed bikes is the Nashbar 105 cross bike. Well in your budget and especially well equipped for the money.