tigertrac swaybars on class A

2002 Holiday Rambler 32 foot workhorse 22 rear end moving around. what they call "the tail wagging the dog" syndrome. Feels like it is so hard to control the rearend. I had shop look at it today. They had 2 different mechanics drive it and they said it felt "normal". I just moved from a class C to a A. It feels totally unsafe to me..lol.....so I am looking at this sway bar. They told me install time was approx. 8 hours. Everything I have seen online has said 2 to three hours. So I am wondering how much difference it has really made for the money and also others opinions on installation time. Thanks