Haven't tried it, but make sure you have time to fully read and understand it before you sign it.
If it is a lease purchase, and you don't have the ability to take the truck to another carrier while it is being leased, I would not sign the lease. That goes for any company offering up a lease purchase program.
You won't truly know about the company until you have made several payments on the truck. If the company sucks, you don't want be faced with either being stuck there, or giving back a bunch of money you have invested in a truck.