I have used Gordon's a time or 2 and it is a free D/L. I have thought about picking up Quickload. You have to enter a good amount of info for Gordon's to be successful. I seem to manage without either for the most part. Just making ladders and checking with a radar. It has helped me with wildcat type loads to make sure the pressures aren't too high since they aren't in the loading manuals. I can see where it might save a little of the costs of load development...but where is the fun in that.