Best Calculator in the price range

I looked around me long and hard, because I next to my "main computer" (Voyage 200) wanted to have a cheaper smaller, in which it is not so bad if I lose him. I am thoroughly satisfied with the product, which is not perfect, but it offers the best value for money on the market.

The following advantages could collect the computer with me:

+ Price (as mentioned)
+ Intuitive and convenient operation
+ Incredible functionality
+ Comes with batteries supplied
+ Also has solar operation
+ There is a separate book "With the Casio FX-991 ES graduation" (although is for the previous model, but still I see it as an advantage)
+ There are blogs and Youtube videos explaining the computer
+ The representation of roots / fractures / integral, etc. is awesome; so I expect for simple calculations rather than with the Casio with the Voyage
+ Is thinner than, for example, a TI-30__ (Texas Instruments)
+ Appears to be stable, I threw him on the first day same time at the university from the table - Originated no crack or other damage.
+ The display is easy to read even in low light.

Negative following struck me:

- Poor processing (compared to a TI-30, which are really well made)
- The "Replay pad" with whom I can scroll through the calculations, takes "up" or "down" at times was as left or right, thus the cursor jumps to the active calculation and the leaves will be interrupted.
- Can not draw any root of complex numbers
- Can "only" 3x3 matrices and maximum 3D vectors calculate
- Can only integrated / differentiated values ​​output (F (x) or f '(x)), but not the function itself.
- Misspellings on the package (I have in the Rezesion also safe but which have, not a global company like Casio :-))
- Brief description

Despite all the negative points of the computer gets full 5 stars because the poor compared to TI processing have no effect until the directional pad on the use, the aforementioned limitations of the functionality of all refer to functions that are not even available in the approach to other computers in the price range, The brief description is compensated by the good documentation on the Internet.