If you will be happy with 4.4GHz, and will never touch it, then I'd be inclined to spend the extra £30 if you are not confident with the overclocking.
That said, it isn't a difficult affair; On the Asus board, its just a case of setting Overclocking to manual, BCLK to 100, Turbo to all cores with a multiplier of 44 (For 4.4GHz), PLL Overvolt to on, and your memory to whatever the specifications state.
At 4.4GHz, the Asus board should do a good job of choosing a voltage for you, but most people seem to be doing 4.4GHz at around 1.25 - 1.3v - some even less!