Searched to the end of the internet..or "more exhaust questions"

[IH8snow]

Searched to find an all encompassing thread on exhaust but didn't get there....

Car/Background..
2001 Boxster S Seal Grey
Not daily driver, just nice day driver
Looking for nice growl, not "tuner" sound


My plan so far...

Topped cat back muffler
Topped test pipes
Easy clamps

Questions I feel as if I need clarification for...

-The Test pipes delete the secondary cats not both, so no need to worry about the o2 sensor or CEL?

-If they delete both sets of cats, how problematic has it been?

-There was mention somewhere of a "Flexible crossbar" that could be loosened to negate the need to remove the rear bumper during muffler install, can someone expand on this or point me in a direction?

Thanks in advance!

Sound clips of anyone running this set-up would be worth 10 internets to anyone