i don't buy from Vados since i had an entire order of 1,000 spikes die only a couple days after arrival (proper refrigeration, storage etc.) and they wouldn't replace it.
i usually order from Knutsons, but you should be aware that they don't charge your card until the order ships. for someone like me who doesn't have much disposable income, i need to know exactly how much money is on my card. when i don't get charged for possibly up to a week, that becomes a problem.
a bunch of the cheaper places don't offer the variety of colors too, so watch out for that.