In the skill guide for Dungeoneering, it shows you how many items you can bind at a certain level. The more items you can bind, the better your experience becomes. In that sense, when you get a hexcrest or its counterparts, those would be good items to bind when possible. In my opinion, rapiers and mauls are the only good weapons to bind for good experience per hour. I'm not really an expert in Dungeoneering, so, someone would have to rate my opinion on that.