i like over the top. just think, even when you buy a new computer next, that psu will be more than adequate. i still have my 350 that i got a few years back, and it's powering my backup comp, which sits in the corner, silent as death.(the psu fan is the only fan in it) but the point of this is that getting top-grade equipment is worth it, because when you do decide to move on, you'll have something you can move on WITH, rather than just starting from scratch. saves you a lot of money in the long run.
just my .02
and you'll be able to say you have a 550w psu
