Mine have never got loose. Don't you know about that red liquid stuff.Looks great!
Make sure you take the correct size 'Allen' wrench or whatever it takes to tighten those highway pegs because they will always loosen up after a while.
On mine. once I settled on the correct position for the pegs, I drilled and tapped through the peg and the highway bar/ engine guard and installed a small high quality stainless steel bolt in the assembly to keep it in place--forever.