I have only ridden solo since I got my TA in 2003. Years ago on my Bonnie I only rode in small groups, I think 18 bikes was the largest. But that was enough to show me the hazards involved depending on the route.
As newt says, city riding is the worst, but out on the 55 mph. 2 lanes has it's own unique dangers. I still remember cars trying to pass us and cutting into the middle of the group, trying to pass slower moving traffic and members of the group taking bad risks to try to stay with the group, and riders being distracted and not paying attention to what the group was doing (I confess, I did that a few times). To me, it just takes all the fun out of riding.
