If you worried about the leather, remove the seats once in awhile & don't put them back in until the seat unmolds.
I had a friend with leather seats that were ruined after about 2yrs of car seats. I had another friend with leather who still after 8yrs of car seats has no issues. It depends on the seat & the install. A looser seat will rub more when the child gets in & out & that ruins any seat, leather or fabric.