Quoted from TheLaw:Call/email all of them and see whom can help you/has best price
I disagree. While this might get you the lowest price, it's not buying you any goodwill playing distros against each other.
I like to forge a long term relationship with my vendors. When supply is tight on a product it might make the difference between getting it and missing out. And it's just good karma.
Take care of your distro and he/she will take care of you.