the info on 5th's site is crap
this is the site to look at
www.TFtunedshox.com
the shock is a lot better now that i have a 600lbs spring. but i might get a 650 as well.
when pedaling seated there is no bob at all but if i get up then there is some movement. but i'm still playing with the settings.
a word about the 5th springs they only recomend 8mm of preload as any more can cause coil bind.
my shock is a 2" stroke but i'm running a 2.25" spring this allows an extra 0.25" 6.25mm of preload (150lbs) but fitting the spring is tight and some form of spring compressor will be required to remove it.
nick