That's what in my mind now. Further calculation of NCD is

Beginning of  PRIVATE VEHICLE
1st Year  0%
2nd Year  25%
3rd Year  30%
4th Year  38 1/3%
5th Year  45%
6th Year  55%

Assume is 4k (flat rate without NCD) premium for car for 6 years. This will be the NCD savings 'lost' if claim insurance instead of w/s.
1000 + 1200 + 1533 + 1800 + 2200
= RM7,733

If add w/s 750/yr x 6 yrs
= RM4,500 saved if don't buy w/s coverage.

Anyone has their w/s broken before ?

Well, look at it this way, if 1 time you claim the W/S cover, you will have top it back. Once claimed, the W/S cover cease effect and you have to reinstate the cover.

So 4 times you claim, you have to fork out 4x 750 =RM3,000.00 I am sure Dr Cermin cost of fixing the 13 holes is less than 3k right?