Definitely worth it if you are keeping the car or have some decent rubber on it. I have a Pedders "shim adjustable" kit in my ED. It solved the outside tire wear problem instantly and also helped with handling, but I gues the new shocks and a few bushes had a role to play in that too.
The KMac "ratchet adjustable" kit has the advantage of being able to be adjusted with the tires on and the car sitting with its weight on the suspension at the normal road height. Therefore whatever setting is dialled-in is what you get in "live" conditions.
The shim adjustable models require an alignment measurement be taken, partial disassembly of the front-end to add/remove shims, reassemble, remeasure alignment (repeat as required). You can imagine how many (few) interations of this procedure most alignment shops would be prepared to go through before they "settle" for whatever reading they have achieved.
As an aside. When the EA's first come out a a few of the more "clued-up" company car owners where I work wanted a kit fitted to their cars. Apparently the garage had been told to NOT fit any alignment kits as it was cheaper to replace a few sets of tires over the period the company would own the cars and that it added no resale value. SHEESH! Bloody tight accountants!