Have no idea where to buy that much seed, and don't have enough experience to really be able to say which is "better." However, I can say without a doubt that my seed starts ALWAYS get huge, as in 10', which is a pain in the ass for me as I'm just over half that height. Clones for me tend to get 3'-5' tall, but the thing with them is they need a good head start. You and I both are right on the edge of when we need to get going on this stuff, but there's no way I can even consider handling 500 starts, whether clone or seed.
At this particular moment, I personally would not work with Everyonedoesit.com for seeds, I would suggest you contact one of the other vendors here at the farm, perhaps logic himself (site admin) and see who might have the kind of stock you're seeking.
