Sharp EL-531 Scientific Calculator

Good build quality and good quality plastic keys.
2. Large number keys: helps to avoid typing errors.
3. D.A.L. allows you to type the numeric input in the lower display and change the sign of mantissa and exponent any time (not possible in fx-82 MS).
4. The Sharp has a Number Base (n-Base) mode for Binary, Octal, Hexadecimal and Pental (base 5) conversion/calculations, which the 82MS doesn't have.
5. The three-digit comma markers are placed on the top of the numerals, avoiding confusion between a decimal point and comma.
6. More memory for input equation and for multiline display (but check the CON number 3)
6. Direct access to statistical values (like mean, SD, sums, a, b, r etc.). No need to wade through menus.