I'd get the Patriot Signature or Corseair ValueSelect DDR400 if you're not going to overclock, and I'd get the G.Skill Extreme or Mushkin Extreme DDR500 if you are going to overclock (they seem to have just raised the price on Mushkin at Newegg, though).
I don't see why you'd want to get really high-end DDR400 unless you're not going to overclock and you've just got money to burn.