I have a ring saw liked dd, but have had a completely different experience trying it :-/
Maybe there's a difference in brands?
I cut a small green branch with it and used my neck knife to whittle a notch on each end and made a Bow Saw out of it.
Obviously it's not comparable to a true saw, but it was serviceable.
I've had mine for years, I believe I got it it from a military surplus place. It's stainless and maybe was a part of some pilot's survival kit?
Might be foreign made as well. I've seen one that look similar but the saw part was different.
Mine was cheap, so If you run across one for a few bucks it might be worth buying and trying out? You might find one that works out for you.