I had a very horrible experience with Sprint. I am sharing my bad experience with Sprint to inform all customers of their unfair business practices.
You should be extra careful if you are leasing a phone with Sprint. They will change the monthly rate and plan mid lease and you are stuck because you are still in the lease. This looks like a trap designed to squeeze more money from the customer. If you decide to close the account, they may charge penalty, lease agreement amount, buying option amount... etc.
If you want to switch over to another wireless company, you may have to pay all the dues including fine and cancellation charges otherwise they will keep the phone locked.
Even if there are disputed charges, they will send it to collection agency and to the major three credit bureaus to make your credit report bad. My best suggestion to avoid this trap is to stay away from Sprint.