I run a Teraflex manual disconnect on my 06 (TJ) Wrangler. Works very well. Made a decent difference just going down dirt roads at sane speeds - allows the suspension to do its thing. My brother uses a manual disconnect on his JK, too.
I agree with Smileyshaun that it is best to disconnect and reconnect on a flat surface, otherwise you'll have binding that may or may not be reduced by rocking your vehicle side to side.