well........they are using a different method ,but each one will work. It sounds like this way would flush the system better(rinse)in a single step, but I dont know if it would clean out everything in the system as good from a cleaning standpoint, Also you have cut your heater core line and leave what sounds like a garden hose t fitting on it. They will both work, do whichever one you want. Neither are hard. It is all personaly preference. Just be sure to make sure it is rinsed very thoroghly either way and you shouldnt have a problem. Just follow the directions on whatever cleaner you get.
