How fast can you go with a trans mounted torque arm?

or should I get a body mounted arm? I plan to dip in the 9's

What is your setup? Biggest concern would be to get a relocation bracket so it gets the T/A off the tailshaft of the transmission.. Don't know if you have an LS1 or LT1, this is the one for the LS1 w/ auto trans...

http://www.customssi.com/cart/index.php?main_page=product_info&cPath=1768_1770_1883_1887&products_id=1342

BMR makes a relocation bracket for the LS1/LT1 taking it off the tail shaft.

What I'm wanting to know is how fast before the trans mounted is no good? or should I just get a body mounted arm?