We have scissor jacks on the front and rear but only use the rears (the fronts are mounted at the bumper to part of the frame that flexes when we put them down--bad position choice).
I have to say that you really can only use these for stabilization. I really wouldn't want to depend on lifting part of the coach with these (they are 7000lbs each if I remember correctly).
Instead I use our
Levelmate pro to find the most level spot in the campsite and then use the lego type blocks to level the coach. The levelmate reads out how much lift each wheel needs in inches and since the blocks are about an inch high it works out quite well. Then I use the scissor jacks to stabilize the coach.
I have two 10-packs
similar to these levelers (Amazon) for the front wheels and one pack of
these levelers (also Amazon) for the rears. All of these blocks fit neatly in the outside storage bay at the front passenger side of the coach.