I have never used the Silky Hayauchi, but that will be the next saw I buy. I have used several of the Sthil telescopic models, which I think is the same saw as the ARS 20' . It works great but has some flaws. The plastic locking mechanism is very fragile and broke on both my saws. But is is not necessary for operation, as the metal spring "ball detant" holds fine. On one of my saws, I eventually had to drill the poles and use a clevis type pin to lock it, but that works satisfactorily. The blade on this ARS is excellent and I am sure the Silky is also. A sharp blade is a must. When it dulls, it makes for slow cutting and more fatigue. So even with its flaws, the ARS/Stihl still cuts great and is lightweight and balanced.
The only thing you must be careful with with any of these telescopic aluminum saws is that they must be handled with care. They are tough but can bend, and a bent shaft renders the saw worthless. I learned this the hard way. Step on it and it is ruined, or even drop a heavy limb on it and it can be damaged. I still prefer it over the fiberglass pole type, as it is much lighter, easier to transport, and easier to use.
I also have a set of the Jameson yellow poles. I have enough poles to go 25' and they are bombproof. I also have the Corona lopper head for these and it also works great. But when I use all four of my poles and reach 20' or more, the poles flex a lot with the lopper, and can make cutting a big limb (say
1.5") a little hard. The fiberglass poles definitely are heavier and will wear you out using them. The higher you cut, the harder the effort. For normal cutting, i will always use my aluminum telescopic saw before I drag out the Jamesons.
I did not know they make a lopper for the Hyauchi. Loppers need a really stiff, non flexing pole so that when you pull the rope, the pole doesn't flex much.
Check out an arborist supply house. Sherrrill Tree has all types and good descriptions of each. Any of these are far superior to the generic Home Depot saws. These large Japanese blades are razor sharp and cut great. Hope this helps.