lift/yoke/stiffener opinions please

[jeo]

I"m looking at putting on a RE 4.5" lift, Advance Adapters 32 spline slip yoke kit and T&J Performance (tandjperformance.com) chassis stiffeners. I've been told this AA slip yoke exists, but have not been able to find it yet.
Any opinions on these products/hints/tips/alternatives would be greatly appreciated.
thanks in advance.

[Lucas]

Just wondering, do chassis stiffeners do anything? Ive seen some cherokees that have done stuff that makes my hair stand up on end and they didn't have any reinforcement aside from the custom bracketry used to attach their axles.
Not bagging on you, just wanted to know what exactly they are supposed to do.

[xj92]

I run the AA HD SYE and it's great. I could feel that it was smoother after putting it on. I've heard good things about the chassis stiffener and I plan on buying one/building one fairly soon.

[jeo]

Lucas
The stiffeners are supposed to keep the body from flexing, weakening the sheetmetal and eventually causing the doors to not line up properly. Also, they are supposed to allow the suspension we pay big bucks for to do the work, rather than flexing the unibody, supposedly resulting in a smoother ride... If you have the August copy of Petersen's 4-Wheel and Off-Road, you can see a writeup on them.
I noticed in your signature, you have an electric fan...I've been considering this. How do you like it?

[Lucas]

I noticed a bit of handdling improvement when I installed my BPI bumper, its super stiff, I guess its tying in the chassis? Where would be the best combat unibody twisting.
I love the electric fan, its quieter and it works well. But im one of the rare XJ owners that like the results. Lucky I guess.