The range should not be a worry, since going into the 5Ghz range would give you less chance of interference and faster speeds, if you configure your router to run ONLY in N mode. Of course, your internet experience is not going to go any faster than it is capped at, but you can transfer files over your LAN at faster speeds.
However, do not run in 5Ghz if you want backwards compatibility for b/g wireless cards. Examples can include friends or relatives coming over and they do not have the new N cards in their systems, etc.