Range

The range is greatly increased.  Now it's at least 80m.  That's more than enough for such a small car.  At such a distance it's hard to figure out what way the car is pointing.

Speed

It doesn't seem to drive faster than before.  I'm a bit disappointed in this.

Control

The original controller was of a very low quality.  The steering of left and right didn't work well.  It's easier to control with the app on the smartphone, although that one lacks tactile feedback.

Firmware

When the car drove out of range, it simply continued what it was doing.  A dead man's switch had to be added in firmware.  One second after reception of the last command, the car will stop automatically.