... Some late model Cessnas switched to tube gear. My Hawk XP had it. It's supposed to be tougher than spring gear but the way it moves wouldn't suit a tail dragger very well.
Some C150 taildraggers use the stock tubular gear.
They often have handling issues, as the tubular gear has no provision for adjusting the toe-in.
The leaf spring gear allows for tapered shims between the gear leg & the axle.
Ted Setzer was part of the design & manufacturing team for the GlasStar.
The one he built is very recognizable as the tail is shaped just like a C180's.
He built & installed Cub-type bungee gear on it a few years ago, dunno if he's still running that gear or not.
Standard GlasStar gear is tubular steel, like the later model Cessnas.
I believe that a lot of builders try to stiffen them up, by installing stiffener / fairings,
so it will only deflect in one axis, like leaf spring gear, instead of every-which-way.
I don't know how successful they are with that.
I'm kind of surprised that the factory doesn't offer some sort of option for running Grove spring gear--
that would seem to be a pretty good way to go.
I've never seen anyone do their own either.