The shocks, springs, and sway bars have much more effect on handling than chassis braces, so get good coilovers and swaybars in place first.
Then a 3 point front strut brace is your best bet, along with a simple rear tower bar if it's a street car. There shouldn't be any adjustment joints in either bars you buy.
And there are ways to make your own braces, do seam welding, and pop riveting of the seams. For example I pop riveted both seams of my door panels between the factory spot welds. That didn't really do much however, when you find yourself pop riveting and seam welding you should cover all important seams on the car. It's also good to make your own front fender braces, not too complicated.
I wouldn't get an X-bar, EM racing 4 point trunk bars, C pillar bars, or B pillar bars as they don't do too much. A simple 4 point welded roll cage does much more for chassis stiffness.