I don't think the radar aspect can be turned off. I drove an MG5 standard for 4 months( which had the simple cruise on/off with no ACC ). 6 weeks ago I upgraded to the MG5LR with ACC and at first I found the "mandatory" ACC really annoying for the reasons you have given. However, after using it a lot I now appreciate the logic of this which is :
1) In the MG5 standard ( i.e. no ACC ) when the car in front has moved out/cut in/braked/accelerated you had to brake/accelerate & reset cruise, especially in busy traffic. Worked well and easy to do, but I found I was constantly adjusting cruise.
2 In theh MG5 LR Sometimes ACC does seem to be on the slow side in reacting, in which case you just override it by braking/accelerating as required, then reset/resume ACC as required ( as you would have done in the MG5 standard ) . Overall less work than standard cruise.
At first I was annoyed by ACC compared with basic cruise but now I much prefer it. My main gripe with ACC is that even the longest of the 3 distance settings leaves me a bit on the close side when doing 60 to 70mph. Maybe some one knows of some way of calibrating to increase the ACC distance ??
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