Richard, My M45 arrived with 600×19 Lesters. The somewhat domed tread profile of these tyres meant that there was fairly limited tread actually on the road. The car’s steering was light. These Lester tyres had a pattern like a 1950s tyre and were very quiet. I replaced the Lesters with Blockley tyres. It turned out that 600×19 Blockleys have a much smaller outer diameter than the Lesters that have the same claimed size. To maintain high gearing for long distance touring, I went for 650×19 Blockleys. They are a much bigger tyre than the 600x19s of the same brand and cost a fair bit more than 600x19s. These big Blockleys are wide, with a flat tread profile and lots of rubber on the road. Thus, the M45 now has very heavy steering and a reduced turning circle. There is more road noise too. I assume this is because of the much bolder tread pattern on the Blockleys. Despite these issues, I like the Blockleys. They look just right. More importantly, they feel secure. In the pouring rain, I like to know that I have serious tyres. Through the process, I have learned to make sure the size you order is what you really want. The difference between Blockley 600×19 and Blockley 650×19 is very significant. More surprisingly, 600×19 Blockleys are nothing like 600×19 Lesters in profile and, therefore, outer diameter. Best of luck with your decision and your car’s new boots.

Michael