I think they would be the quickest and easiest ascent entry system out there.
I use the dual handled/dual ascenders, which is, in essence, one half of the mar bar system. As a professional arborist, the big drawback is whatever you carry up into the tree, you either have to carry it around with you, hang it and get it before you come back down, or lower it out of the tree while you're up.
The mar bar can do SRT or a stationary doubled rope, both 1:1 systems and the shining glory of the system is the convenient handles and that you don't need to know how to footlock. It's very easy to learn on, I would have to assume.
For Arborists, there is the issue of it doesn't stow conveniently on the saddle, as in carrying it around once you get up there. Kinda bulky, and we have things that rec climbers wouldn't have like hand saws, chain saws, a rack of biners, a few slings, trees cord and the all-important flipline and adjuster. Even ear protection muffies that you might clip on to the saddle while not running the chainsaw. All this stuff needs to be clipped on to the saddle for use as needed, generally a fairly full load for the a climber/cutter/rigger. Schlepping around the mar-bars, things may get a little tangly and difficult to manage, which in our world can equate to 'less safe'.
But for canopy entry in recreational climbing, totally different element. I'd have to say the mar-bar system could quite possiby be the best current system in the world for what you want to do, or even for Arborists who so on-rope ascents at 30 meters and beyond.
Before you go using them, do consider how you plan to come back down the rope.
My wife's caving rig is a mar-bar-esque version set up for single rope. |