not sure about that PSU. seems it would be better to grab a 650-750W now, and then upgrade it when you need it, as prices on higher wattage PSUs will have undoubtedly dropped by then. where are you getting your combo deal? NCIX canada has that same deal, but they also have a P182 + Antec 650W PSU for $165. how's the A8N in your wife's system doing? i hate that motherboard with a passion, had no end of problems with mine.
I've never had an Antec PSU that's worked (or didn't die within 3-4 months)... might just be my bad luck, but I'd much rather pickup a Corsair or PC Power and Cooling PSU.