Another thread was discussing ways to go up the mast, ie, a ladder vs
bosun's chair vs rope climbing systems. I have climbed miles of rope
whilst vertical caving and have used cable ladders for long distances
and loop type ladders more commonly called "an etrier" by climbers. I
normally use my vertical caving gear to go up the mast.
An Etrier is effin difficult to climb for more than a few feet and
basically all you do is dangle and thrash. No way I'd go more than
about 12' up on one and even then I'd want to be against the mast or a
wall.
Cable ladders: They require proper technique. One foot goes in
frontwards and the other foot goes in backwards (heel first) from the
back side. Otherwise, you end up leaning backwards too much. Not
very easy to use.
Mast steps: Snag halyards and sheets.
Various rope climbing systems: These consist of mostly mechanical
ascenders like jumars, or gibbs-like ascenders and a seat or harness.
I recommend you check with caving suppliers, call and ask for what
they recommend for a non-caver very occasional use.
Bosun's chair: Not bad but does require that somebody else has your
life in their hands which I do not like.