Where did you get the thermistor that is in the hot end you have? If you can find the correct table for it (or calculate it) then you'll get much better results.
You may find that the calibration is still off (eg: 240 when it's say 200) and that your temp readings are not as accurate as you'd like.
You may find that the calibration is still off (eg: 240 when it's say 200) and that your temp readings are not as accurate as you'd like.