I never believed that the brace supported the turbo on the stock header. It's actually the turbo bracket that does that job. 1500 degrees and stainless steel is as soft as butter. So, the 30lb turbo, and downpipe being tweaked by a twisting exhaust and a vibrating motor all supported by a glowing header.
I fabricated custom independent brackets to support my turbos. It gave me some piece of mind. I had the headers coated and didn't want to go back to weld up cracks later. Also, I can easily remove a header and leave the turbo right where it is still connected to the down pipe.
I've had this set up for about 8 years or so. A lot of miles and no cracks. Just something to think about.