I'm going to buy the QS8 soon, but the Axiom stands are too expensive so after shopping around for a bit I found this stands:

http://www.standsandmounts.com/index.asp?PageAction=VIEWPROD&ProdID=4281

Do you think I can mount the QS8 with that L bracket backward so the speaker is hanging out instead of sitting on the bracket? this stand looks hefty and I can also fill it with lead shot for more stability.

I would be very, very concerned about the stand falling over. The QS8s are not light speakers.

if i packed the stands with lead shot wouldn't it help stability? looking at their website the stand weight 13 lbs/ea, about the same or slightly heavier than the Axiom stand:

http://www.lovanusa.com/product_info.php?cPath=3_5&products_id=77

It's the base I'm concerned about.

The thing to consider between this stand and the Axiom one is where the weight is supported, not simply how heavy the stands are. This stand suspends the speaker 'beside' the support beam (the way you want to mount it) and the weight of the speaker is trying to tip the stand over. The axiom stand holds the speaker directly above the support beams, so the weight is applied directly downward and is not trying to tip them.

The next most impressive thing about the QS8 is it's weight.

I am very sure that this stand would not work at all. And with any kids or pets around it could turn into a very dangerous weapon. The support looks far too small in diameter to hold any effective amount of lead shot near the base of the unit. In a word "no".