Hi MS & Troy,
The only thing the rubber is designed for is quietness over concrete and nothing else. It's not going to do anything on the grass except tear up the edges when you turn it around, thus why they originally had rounded outer edges.
I'm not trying to burst your bubble, but this was merely another one of those buck making ideas someone came up with. The question is, why don't all the pro machines have them ??
In saying the above, the Series One 20 inch 45's had that extra 3 inch section between the two roller halves and they do nothing more than tear up the freshly cut grass when you turn the machine around as it doesn't turn due to it being at the centre of the turn around point of the mower, while one of the halves turns one way while the other turns in the opposite direction and the centre piece stands still. Not good in confined areas of the garden as you always have to take a wide arc to avoid this issue. the same will have to be done with those sharp edged rollers.
Cheers,
BB.
