Why not use both? That is vat the daddy does. Its funny when we start competing with each other...he usually pwns me when it comes to LCDs, monitors, CPUs, mobos etc. but I usually pwn with removable media, memory, hard drives, video cards and other 'consumer' peripherals.
EDIT: Unless you're buying significant volumes (i.e. my dad just bought 35 Geforce FX 5200 cards the other day) and you have a good rep and good negotiation skills, stick with NewEgg!