Both the Gardener and the Rover are hard to move around, you get it on the wrong angle and they stop moving, wouldn't be fun going up a hill.
That's very interesting information there ... and it makes sense.
Bargain on the Sabre!
I might add, One of the claimed advantages of the off-set wheel design was that
it
prevented 'scalping'. I must say, I have never accepted that argument on
smaller width-of-cut rotaries. And in the USA, where they prefer higher cut lawns,
it made no sense at all.
I might also add that, today, American mowers have largely followed the
Australian tradition:
https://www.toro.com/en/homeowner/walk-behind-mowers[
p.s. I love their 'Lawn Striping System].
They have adopted the four-square chassis - but still persevere with
multi-point height adjusters

For me, this makes no sense, since the introduction of power edgers in
general, and specifically, line trimmers.
All very interesting.-------------------------
Jack