I have a 3.5" BDS lift front and rear. I broke the front driver side on Yankee Boy Basin above Ouray, Colorado. Had to go to Durango to get the replacements. Warranty couldn't be used at that time (due to the remote location and the dealer was not a BDS dealer). I didn't want to drag the leaf springs home as it happened during the first 2 days of a week long vacation. I was headed to the New Mexico back country.
Last trip to Moab, I discovered the driver side back had a broken leaf spring (lowest one). I am working with High Country 4X4 Performance to get the warranty honored this time. I have to pull the old ones (hopefully soon as I bought the replacements already) and then have the dealer send them (at my cost) to BDS. Once BDS inspects and gives a return credit I'll get compensated.
Originally, I installed the lifts myself. I went with the recommended 4 degree shim. I started to go through u-joints on the drive shafts soon after. I changed that shim out for a 6 degree aluminum shim and that stopped the u-joint troubles. I find that the aluminum shim shifts a lot so when I change them out I'll install a Poison Spider steel shim.
I do like the BDS system. Overall, it gave me 4" of lift on the Mighty YJ.
The 2-step shock absorber system make the first few trail runs interesting. Once they are broken in, they are marvelous.

This was taken on Crystal Mountain near Ft. Collins, Colorado soon after the lift was installed.