Scot, based on your posts it looks like you already made your mind up on the cal tracs.
The Unlawful system is nothing like the street links. I see a lot of people racing and cruising with the alterkation front ends but havn't seen anybody racing with the rear ends. No offense but it just doen't look like it can take a lot of power. I am no engineer so it just my opinion. The Unlwaful system can take a ton of power where the street links seems to be more for street use.
The cal tracs do work for racing but not so good for street use, you are basically making the front half of your spring a solid link. This can and sometimes does tear parts of the car if a lot of power is applied to a weak or rusty car.
Make sure you have a solid body at the connections for the springs!!!
Like any system, cal tracs are just not as simple as bolting it on. There is going to be other stuff you need to change and upgrade. The Unlawful system is complete when you get it, shocks, springs, bolts hangers, everything you need to put it together. All the little stuff adds up. I needed nothing else for this system.
You can adjust this system to leave flat and maximize traction, or pull a big wheelie if you want to. It is all how you set the instant center and can be changed at the track in minutes, literally!!. Cal tracs can't change the instant center, only stop the axle wrap.
This is very streetable as well!!! My car handles like it's on rails.
This system is not a back half but gives you many of the same advantages. One thing about it is that you can easily go back to stock on a valuable musclecar, you can't do that with a back half.

Again, this is just the opinion of a guy who uses a particular system and likes it. It has improved my car by .20 second in the quarter.
I have my flack jacket on so fire away!!