I endorse your advice to "GS" regarding travelling too slowly on motorways. I recently travelled south on the M1 from Jct 40 to Jct 37 and, arriving at my destination, found that my nearside rear tyre had punctured. My car is a Jaguar S-Type 3.0-litre with a spacesaver spare wheel, restricted to 50mph, which I fitted for the return journey. I spent most of the time looking in my rear view mirror to spot HGVs approaching from behind to warn them of my slow speed by flicking on my hazard warning lights. The vast majority of the overtaking drivers expressed their appreciation of this by giving me an answering flick of their hazard warning lights as they pulled back in front of me. Given the same set of circumstances occurring again I would definitely choose the alternative non-motorway option for my return journey home.