Lease Purchase schemes from large companies with a CPM vs percentage are based around placing the maintenance, purchase, and operation costs on the leasing individual, while increasing the pay only so much that you end up making minimally more, if any more, than your standard company driver. This arrangement ensures that you remain beholden to the company as you cannot leave with the truck from their employ, should they fail to keep you running, and you will have to run longer for them to "catch back up" on your overall payment schedule and/or pay back anything the company loans to you for any major repairs.
Most companies will also not lease you brand new equipment, but you will have your pick of low-spec company powered trucks with all the associated equipment to maintain at your expense, with higher miles than if you were a company driver, and to add onto that, previously driven BY company drivers with minimal concern placed towards idling effects on emissions systems and the like.
I wouldn't enter into a L/P agreement with pretty much any major carrier. You're paying more than they did for the truck, and it's going to be a low end truck at that.