CONS: The major drawback to an excavator is the travel speed, so if you have long distance to travel between or to uses, it can consume a lot of time.
Tracks do wear out and are expensive to replace.
NO LOADER so you can only push a small amount of dirt with an Excavator.
It is basically a one function piece of equipment. Just like a zero turn mower that mows better than any other, an excavator digs better than any thing else but that is all it can do.
PROS: You wont ever have a flat tire on an excavator so it can go into nails, thorns and other sharp objects that may ruin a tire on a tractor.
You can swing 180 degrees in both directions on most excavators so you can dump your spoils a long way from your digging, most helpful when digging out a pond or ditch.
You can reposition the machine much easier than a TLB and no moving from seat to seat or spinning the seat around to move it.
The speed of operation is usually much faster on an Excavator than a TLB or even a commercial backhoe.
As for uses, with a hydraulic thumb on it, you can use it to pick up almost any object (rocks, branches, stumps, fire wood etc.) and gently place it where ever it is needed.
If I had a lot of digging to do, I would look at an excavator then when most or all digging is completed you can sell it for what you gave for it as long as it has been well cared for. Then buy a TLB. Personally I wouldn't be without some kind of digging and loading equipment