Similarly for the refill process - it is absolutely painless as well. Budget Propane watches our consumption and simply keeps the tank topped up.
We don't us much gas so I think it really comes down to a visit in the Spring and then on in the Fall. I think the cost of the rental of the propane tank is more that the annual cost of the gas!
We can monitor the level of gas we have by popping the top of the propane tank and looking at the attached guage (you can just see it at the bottom left of the picture).