with the shocks upsde down you will get a small area of freeplay,,undapened movement..not noticable on the rig,,,but if you have the shack upside down,,and wait over night and check it in the morning you will see what I mean..the shaft will move up and down real easy..it goes away after the shock has been cycled but not a big deal from what I've seen..But i could see the valve getting worked over in time..some shocks it does not matter..so do,,some don't..most of the newer name brand off road type shocks I don't think it matters much anymore..