I am currently running the 5100s set at 1.75" with FJ TT Springs up front. I currently have a 2.75" lift up front. I am running the FJ TT Rear springs, which gives me a .5" lift. I went on a trip to Utah this past weekend, and my rear sags with load and passengers. I do plan on getting the Toytec 2" Superflex springs soon to help with the sag. Will running FJ springs in the front and Toytec in the rear make the ride uncomfortable where I have to replace the front springs? I wanted to see if anyone has experienced this. I off-road here and there, but 75% of the time it is on pavement. It is comfortable now as my DD.