i think an issue here is people do not understand the difference between a backhoe and excavator.
a hoe has the operator sitting stationary with a range limit of something less than 180 degrees, more like 150. the boom generally does not have a lot of reach. the operator has poor vision as the bucket is rarely in front of him. it is digging on one side and dumping on the other, it is ok for digging shallow ditches or trenches and small holes. any hoe that fits on a compact or mid size tractor is severely limited because they simply do not have enough reach to dig very far away, very deep and don't have the swing to get the dirt far enough away from the project. these limitations are why a backhoe is constantly repositioning, the operator cannot see, cannot reach the job and when he can reach it he can't get the material far enough away.
an excavator, can rotate 360 degrees, digging and dumping at any place in the rotation. it will have a longer reach and most of all the operator always has the boom in front of him to see what he is doing without turning his head or body. it has better visibility, more reach and more swing.
don't get me wrong, a back hoe is a fine machine but they are far better suited for small, quick jobs.digging a shallow trench, cleaning around a culvert, installing a water hydrant and then quickly filling the dirt back in with the same machine. they are not the machine for digging long ditches or cleaning ponds.