Yeah, I've also always ordered from onlinemetals.com. Great place! I was wondering though, I've seen 6083 al or something like that... Someone said it was STRONGER than 7075... Any word on that?

Wrong. 6063 in it's highest temper is only about 27000 psi. While 7075 peaks at almost 84000 psi. 7075 is THE strongest aluminum alloy period.

Which is why 7075 is considered aerospace grade. You can expect that when something is approved for aerospace applications that it is the best of the best (Eric Roberts not included in this statement).

good info here http://en.wikipedia.org/wiki/Category:Aluminium_alloys about tensile strength etc.