The P-11 that I rode on test at N-V was about as far away from a "nice bike" as it was possible to get. It was very sharp-looking, I must admit, but not a "good ride." We got it sent to us from the US to test because of a big US lawsuit over the death of a rider in a desert enduro in California. Nobody at N-V had ever heard of the P-11! When we dug into things a bit deeper we found that the California branch of the US importer of AMC brands decided to make the P-11 by adapting a Matchless 500 scrambler to take an Atlas 750 motor. It was very popular in Southern Cal, but had never been an AMC product at the time. the story we got was that the fatal accident resulted from a high-speed "tank-slapper" which threw the rider over the handlebars. He was then run down by his own bike.
The bike was brand new (12 miles on the odometer) when we got it, and I got the task of breaking it in for testing. I did about 4000 road miles on it, riding 8 hours a day. It was a scary thing to ride, particularly at 75 mph and less. It had a long-wavelength directional weaving habit which got wider with speed and at 75 mph it was about 2/3 the width of a freeway lane. After riding the Commando a lot, I also found the vibration difficult to live with. We started investigating to find the cause of the weaving, thinking it had got so bad in the US accident that it pitched the rider off, maybe with the front wheel digging in on the desert surface.
Just as we were getting started, we got word that the US case had been dropped (maybe settled out of court?) and our test program was cancelled. I think the bike was still in the Experimental shop at Wolverhampton when N-V rolled over and died. Maybe someone transferring to the Andover Norton facility had taken it down there, unless someone from Plumstead decided to take it on as a production job.
I'd emigrated by then. Since I didn't keep in touch, I was surprised to find that the P-11 had gone into production in the UK.
Any and all help is highly appreciated.