I liked that is was easy to use. it allowed multiple inputs from different sources, so there wasn't anything wrong with this package if we didn't have any other way! There were really no downsides either; everything worked pretty well in terms of calculating our required values which gave us more confidence than using some online calculators would give us. If anyone just wants an extremely simple calculator then they could probably get away without another tool entirely as long as they understand how much value R has over traditional tools (I don't know why people still write Excel files!). We needed something quick because most companies want fast turnaround times at minimum costs while maintaining high accuracy levels in order to protect themselves legally against financial losses due to product defects.