i ride alone unless i go to comps or england. i work on my technique and smoothness when i ride on my own, and leave all the progression to whenever i ride with people. i was stuck at 44" for months, left for england, had 47" in a few days. i can't seem to progress much when i ride alone as i am too scared to push myself. as soon as i ride with somebody else, i really give it real effort, and suddenly i go much bigger than i though i could.
i like riding on my own, it feels rewarding. i do prefer going with someone else though...