I used these to replace the old 100# lifters under our king bed. They worked great. 100# elevators used to take one person to hold the bed - heavy lifting and another person to get under and take blankets/sheets etc. I suspect the old elevators were worn out too, but still had some compression. However, with these 150# lifters, one person can lift the bed with one hand and it will remain upright. Then it's easy to slide. I haven't taken it on trips yet, but so far I'm very happy with it. They fit our old mounts so I didn't have to take them off. I just lifted the clips to remove the old ones and attach the new ones. I had trouble with one of the clamps but I think it was more of an operator issue as I tried to do it myself by raising the bed and changing lifts. should have helped.