Pros: Have changed to be better design every time yet keeping good cutting power.
Cons: unsafe use
A tool that I had for years in different forms is the Ames brand Tree Trimmer. It was also sold as True Temper that is now ownded by Ames. It has both a lopping side and a saw side. It's an extremely handy tool to have for light tree work that's above the eight foot mark and below 18' or so. The added height of the user and extended arms along with the 12' to 14' of this tool allows such height.
A Changing Tool
My newest Ames trimmer with a fiberglass handle has evolved over the years. My original had a wood handle and wooden extension poles. The newer poles are about seven foot closed but extend out to 12-14' depending on the particular Ames product. The wood trimmer I had used two additional wood poles that gave it the furthest reach of all the pole trimmers I owned. The telescoping properties of the newest trimmers are easier to apply and I don't have to take the time to "build" it.
The newest fiberglass handled trimmer is safer than the metal trimmer I had. It's a tool that was loaned to someone and is definitely somewhere, but where I don't know. The fiberglass does not conduct electricity, an always present danger when reaching high. I have had all three products over the years. The fiberglass is the safest and best against the elements.
Lopper One Side
The mechanics of the saw and lopper has remainded relatively the same over the years. Every lopper side used a rope as a lanyard that opens and closes the curved blade of the cutter. One reaches up, hooks the receiving end on the branch to be cut and then pulls on the cord. That pull pushes the blade toward the steel receiving end, cutting the branch. I effectively use the lopper on branches up to two inches in thickness. (depending on the type of wood) The compound pulley of the fiberglass trimmer makes the transfer of power easier and smoother to operate.
I use a shot of WD 40 to keep the action running smooth. I do have to take of small "strings" from branches that collect from green wood.
Saw On the Other
Using the saw side is easy too. I generally give a slight cut under the branch, below the main cut from above so the falling branch doesn't peal away the bark on the bottom of the branch as it falls. This also allows for getting the bulk of the branch down and then making a cleaner cut closer to the tree trunk so as to not have unsightly "coat hook" branches sticking out.
The coarse teeth on the saw allows for quick clean cuts with little effort from below. The blades are sharp! I also give these blades a shot of WD 40 as I keep it outdoors all year.
I can recommend Ames (True Temper) Pole Tree Trimmers for high work from safe on the ground. Watch out for saw dust getting in your eyes and especially for that branch ya just cut.