I'm just curious, if you couldn't get to a pull-up bar would manna training be a good substitute? It works your upper back, triceps, hips and abdominal core doesn't it? I'm planning on going traveling at some point in the near future and taking a pull-up bar with me would really put the weight of my ruck-sack up.
I'm only on the easiest straight leg L-sit variation at the moment and was planning on trying to wait til I can get the hips forward variation of L-sit before starting manna training. Does that sound sensible?