I would like to give the response of 2 newcomers to this years GP, me and a club member, who shot at Newbury and for the first time coming across 15mm kills.
Both of us missed the one on lane 6 (i beliieve just before the sillys) me for windage and my club mate 'pulled' his. We both enjoyed the fact that they were not stupid distances and not at the maximum either. In fact the closest one was out of focus slightly but challenging enough with the kill and face plate merging with paint that had been knocked off the faceplate.
As for me it had been a few years since I shot a 50 shot course and my club member had never shot a 50 we both found that the balance between the course length and reducers to be good.
Would be interesting to find out what the sort of ratio is on the number of hits per 15mm target is for this and the previous rounds and to see if the ratio becomes better as people practice on the 15mm reducers more.