Is a rear strut bar and a rear sway bar were the same thing? If not, what is the difference? Also, if l were to pick one, would you get the front or rear, or would that not make sense? Also, what is the difference in ''stiffness settings''? Big difference or no? l drive fast and hard but I am not a racer.

WTF? there are no disadvantages to adding a sway bar.. never.. dude go with the GReddy front and rear or monster motorsports rear and DC sports front.

also while your in the area of suspension a anti roll kit (aka sway bars) would be great as well, for that l recommend eibach complete kit with bushings for 350 listed below are some great websites for tuning your tC

Sway bars go underneath the car. A strut bar in the rear goes through the trunk/hatch (cutting into trunk space). In the front it goes neatly under the hood.

The sway bar is purpose is to increase roll-stiffness with only a minor increase in wheel-rate (as compared to increasing roll-stiffness with springs). Roll stiffness allows the outside wheel to bite harder in turns. In extreme situations, the inside wheel can lift causing understeer. For the tC, the popular sway bar offerings make sense but for racers, sway-bar tuning tends to be a trial-error process of determining the right stiffness for their setup.

A strut-bar is actually a structural piece that tie the strut/shock towers together (left to right). It prevents them from deflecting inward/outward in harsh driving. It also minimize twist that comes from extremely harsh driving & may prevent the car from gaining some of the sqeaks/rattles that come from age. The only possible disadvantages that l can think of is a minor increase in vibration/noise transferring into the cabin.

In general, you're going to experience more performance from swaybars than strutbars. l recommend finding the limits of the car is stock setup (in a controlled environment) before upgrading. That way, u will get a much better appreciation for the changes.