Well the steering stabalizer isn't really needed... Some people wont touch 'em, cause they tend to hide wearing out suspension components.
How is the quality of their lifts? Most people swear by skyjacker or James Duff, most other brands have been proven too weak.
Looking at their website, it looks like the passenger side beam is a drop plate, that reuses the stock bracket... you have to modify the stock bracket if you dont want to punch a hole in your diff when you bottom out the front end. Also, the pitman arm they provide looks about 3.5" too short for 6" lift...
And the back looks like Add-a-leafs and big blocks... Big blocks and add-a-leafs are both no good for flex.
I am piecing together my lift from junkyards, and the classifieds off this site... So far I got myself brackets for $130 shipped, and 4" lift coils for $80 shipped. If I waited a bit longer I could have gotten 6" coils for only $90, but oh well. Free 2" ranger blocks from a JY, and some explorer leafs for the back... $40 for the pair. If the blocks/explorer leafs are not equal to the front with the 4" coils, Im going to get some belltech 6400 shackles, they're about $50, and then use washers on the front if needed to level it from there.
So without shocks or camber bushings, Im in for $250-300, depending if I end up needing shackles. To make 6" in the back, I think an add-a-leaf would do the trick, which are $40 from Summit...
Add $150 for shocks, $80 for camber bushings, and $200 for the FA600 extreme pitman arm you'll need anyways...
$760 for quality parts, some used some new.
edit - my dads friend owns a suspension shop, so I will not be paying that much for shocks or camber bushings, but you get the idea...