Yes
No
Sometimes
Perhaps
Depends upon the length of a piece of string.
In general Oregon blades are better, better steel usually thicker to boot.
Stens blades tend to be from OEM suppliers and generally identical . however I have gotten some that were thinner steel
Rotary blades that I have used were all made in Mexico and seem to be identical
Prime Line blades have never been tried so I don't know.
Unbranded Chinese blades all look the same but on several occasions my customers have had one fail in brittle mode when they hit a star picket, tree root, rock etc
These were Original blades from the shop where they bought the mower and appear to be made from plain high carbon steel not boron alloy steel.
It is hard to access the quality of blades fitted to customers mowers because I have no control over their use
However the landlord uses 2000 series Cubs on the farm & for those we found the Stens blades came a close second to Oregon blades and both outlived the MTD blades by quite a long way.
So if you are a customer are looking at blades bought on line, have a serious think.
Blade breaks & goes flying off into the distance injuring a person or their property .
Is there an identifable person to sue or will the buck stop with me ?