the last time i was in a position that i oversaw hardware purchasing... you get better deals based on your overall spend. after we had spend 250k we got a new sales rep that had access to offer us lower pricing, same thing happened once we breached the $1m mark. new sales rep and pricing went lower. In fact, our first sales rep couldn't even make up a reasonable deal at $80k because he didn't have access to that level of discounting.

usually i always send everything back and tell them to do better.

my biggest gripe about dell pricing was no line items, just a bottomline price. so i couldnt tell which things i could save money on by sourcing them elsewhere(ie: larger drives, large amounts of memory)