I use 'ThreeBond 1211. Make sure you wait for 72 hours after assembling it before running it! make sure you remove all of the old material and the pipe is clean and oil free.
Proseal 'Copper XS Hi-Temp RTV Silicone Instant Gasket' is also very good.
The Proseal is good for 370 C.
If your Berg has the ball & Socket mid pipe to tail pipe interface, make sure they are fully ingaged. My 04 didn't engage fully so I had to slot the frame brackets.
Joe