Outer Limits 4x4 Board

are they any good what extra mods are needed?
The reason i ask is that they are cheaper than a 5link or drop arms

It depend on what you are after from your truck,
if you are after all out flex than an x-link will be great, ideally you should also fit drop radius arms to the setup to make it handle okay on the road.Rotating the diff for caster correction is only half the equation as the rear of the radius arms will always have pressure on the rear bushes and this is where ideally you fit drop radius arms as it will correct this problem. Also standard radius arms are common to break.Cost starts adding up.
You will find x-links , 5 links and Superior high flex arms all max out the full shock length that can be fitted in a nissan anyway.
Standard drop radius arms will NOT get massive travel as they "max" out the bushes first and this binds them up. they do not travel any more than standard arms although guys "claim to get extra travel" RTI tests done many times different brands
5 links are also good for all out flex, both 5 links and x-links are not very good at handling high speed cornering without being pinned or sway bars fitted and from my driving experience ( i have used them all) drop boxes, x-links, five links , standard drop radius arms and the new high flex superior drop arms they all have their place for different applications.
If you are after a near perfect handling setup for road as well as offroad than look at the drop boxes as they will correct the radius arm geometry back as nissan designed it with the rear of the arm low behind the diff so as this supports the diff fully this in turn will allow the impact of bumps and rutts to be transfered up the coil and shock NOT a % of the force to be transfered up the radius arm. This is why 80-100# drive so nice as they already have a type of drop box from factory.
The best allround application i have tried to date is the Superior High flex arms as it will give you maximum travel within the shock tower and still retain a close to factory ride( about the same as any other drop radius arm).
From the post that has been on this site they have been winning more top placing per event than any other application .
This is only my opinion and you should test drive trucks with the different links fitted yourself, as guys who have only tried one or the other really do not know the difference.
Have a read of this post and there should be other posts for x-links and five links
Hope it's of help
http://www.outerlimits4x4.com/phpBB2/vi ... highlight=