the lt and trx are basically the same, some say the lt is stiffer ?
i know the trx has an offset rezzie and requires cutting off a frame mount and cooresponding rear fender plastic tab,
the yfz is way too long, IMO
never heard of anyone using the kfx.
the 400ex is the simplest to do, and is a good shock.
all require the KOR bushing up top, or home brewed bushings