any performance increase, if any at all will be too negligible, it just isn't worth paying up $250, let alone $95. now if you were planning to do some extreme OCing, maybe. basically the board doesn't offer any performance benefit outside of it's OCing capablity.
keep your motherboard if you're not looking to OC any further than you already are (if you have OCed). if you want to upgrade consider a GPU, or an SSD.