good mate of mine did this and got the gold certification..
said the lessons and exam were worth while.. and while valid the certification gets you a discount on your insurance.
he did make one interesting comment about the exam itself
he said that if you are out with the instructor and you fail to make an overtake where one clearly exists that you would not get the highest result possible... apparently the thinking behind this is that sometimes you are forced into a situation where you have to overtake, and this is what the instructor is looking for. (Odd but I can see the logic)
He took a few of us out and explained the main theory behind what he was shown, gave me some tips about reading the road, cornering, road positioning etc and I found it improved my riding significantly.. and made me a faster (corners) and more controlled rider.
although when he let his insurance lapse due to injury
and he went to get re-insured, he couldn't get insured on any high insurance classified bike.. even after 13 years of biking and insurance prior to that..
it seems that the insurance companies put more stock in a no claims bonus than they do a gold certified rider...
these are the type of current grades they have
Grade 1
Rider exceptionally skilled, rides flawlessly at all times and in all conditions.
RoSPA Gold, RoSPA Silver, Police bike riders.
Full licence rate less 30% (55%)
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Grade 2
Highly skilled and very safe rider in all road and weather conditions.
IAM advanced, RoSPA bronze, AON/AXA Skills Assessment pass with a minimum of 38 points.
Full licence rate less 15% (40%)
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Grade 3
Full or provisional licence holder that can ride safely under all normal conditions, on all road types and can overtake safely.
AON/AXA Skills Assessment pass with a minimum of 24 points.
Full licence rate less 10% (35%)
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Grade 4
Provisionally or fully licenced rider, safe enough to ride unaccompanied in all normal conditions.
AON/AXA Skills Assessment pass with a minimum of 14 points, full licence.
Full licence rate (25%)
my 2p