I needed a calculator that would be more reliable than my little battery operated ones so this seemed to be a good choice. It is much bigger than I expected and to do some of the calculations, the instructions are a little confusing as the languages are inter-mixed. That is the reason for the 4 stars.
I had a much older Casio FR-2650 and I love this one so much more!! All the keys are in the same place, which was the reason I picked it, but the screen and digital numbers are so much bigger & the keys are quieter. I would highly recommend.
Cons: poor user manual, see quality issues in my comments below
1) Manual is written for several different countries and languages and in a very small typeface and contains little useful or understandable information in English, at least.
2) I set the decimal place to read/print to 2 places. Despite the setting, unit will continue to print and read out to the maximum 6 places for several calculations, then suddenly start reading/printing out at 2 decimal places.
3) Several times, unit will not respond to key inputs - will not display or print inputted key information. Repeated pressing of a number or function key will eventually restore operation.
4) Came into the office one morning and found about 2 feet of blank paper on my desk dispensed from unit. Unit had been turned off all night but plugged into the wall. At first I thought someone had been playing around with the unit the previous night. However, after I turned the unit off later that day, I then heard a clunk and noted the display flash on and off and the unit advance (feed) the paper as though the feed button was pressed. I watched the unit and it continued to do this every 2-3 seconds. The unit was tuned off but plugged into the wall. I now knew what had happened during the night. Paper kept feeding from the unit until I unplugged it from the wall. Unit is back in the box and being returned to my O-Max store tomorrow.