Well I did some testing you may be interested in.
The R on the plug stands for risister type, so on my multi meter the plug reads 6.5 ohms resistance, a bosch W 7 dc non resistor type I have reads 0.29 ohms. The leads I have are 5k-ohms, when i put the multi on the lead with the WR 7 dc conected to it the reading is 10 ohms!.
With the W 7 dc and the same test I get 5 ohms.
So based on this it would be a must to run non-resistor type leads with the WR 7 dc, thus you will end up with only 5 ohms too the plug spark not Ten.
Now to fined some non-resistor type leads :-/ , I will run the non-resistor type plugs till then.
Hope this helps you guys too

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