OK we have a Rear sway bar (RSB), a front sway bar (FSB) and a front strut brace (also confusingly FSB). Strut bar goes under the hood and conntects the struts, sway bars link the wheels.
TRD makes a RSB and a Front Strut Brace. Whiteline makes a Front Sway bar and a Rear sway bar.
The front strut brace upgrade doesnt do much of anything, except makes the strut brace more angular so that a supercharger can fit under it; it doesnt really do anything for actual suspension improvement.
The rear sway bar is the sweet one. The one TRD makes lets you choose, I think, either 19mm and 21mm thickness, depending on which holes you use. The Whiteline RSB only has a setting for 20mm thickness, so its right in between. Rear sway bar makes the ride alot more flat in cornering, and decreases understeer, which is the biggest cornering problem with FWD cards. You can get one from
www.kinderhooktoyota.com - thats where I ordered mine $150 shipped. The guys name is Eddie and hes a good guy. You'll find him somewhere on the TRD parts of that page.
The front sway bar is made only by whiteline. The problem with thickening the front sway bar is that it stiffens the front so that it brings understeer back. Granted the ride may be even flatter, but if the goal is better cornering, the FSB isnt really worth it.
Id imagine the difference would be flipped for a RWD platform - the front sway bar takes away all the oversteer problems, so that ones most important.