i slam more by myself. if you're skating the same obstacle as your crew you get to rest in between tries, which helps. I find it harder to stay motivated by myself. even skating with one other person is preferable. also, if you really fuck yourself up, you don't have to crawl to your phone/nearest doctor, your buddy can help you out.
edit: i'd skate with you if i was in your area, but i'm on the other side of the pacific ocean.