Ok - the decisions I made on purchase/use of a rear blade. My original rear blade was Land Pride and weighed around 400 pounds. One pass down my driveway showed that it was WAY too light for any type of summer work. It did, however, do well in the winter on snow.
2009 - I upgraded my tractor and bought a brand new Kubota
M6040. I already knew I needed a new, heavier rear blade. So I looked at what was available here. Land Pride and Rhino. When I spend that much money - I want to "lay hands" on the product before I sign the check.
I'm sure the two dealerships thought I was a little "light in the loafers". The way I lay on the ground to look at the underside of the rear blades. The way I checked out ALL the grease fittings. The actual thickness and reversibility of the cutting edge. I'm sure they considered calling the men in the white coats.
In the end - my decision was a Rhino 950 - 8 feet wide - 1050 pounds. They also had a Rhino 1250 - 10 feet wide - 1650 pounds. The 1250 was, simply, too big for my tractor.
I have never had any reason to regret this decision. It is just the correct weight to break the crust and dig into my summer driveway. It easily offsets and depresses to clean out my driveway ditches. AND - as far as snow - if we ever get any - it will do well there also.
A note on snow. If you ever get snow and your driveway isn't frozen, rock hard, yet. Reverse the blade 180 degrees and go forward. It does not blade the snow quite as well. However - it DOES NOT blade the surface gravel into your driveway ditches either.