When I was a teenager living at home my dad owned a Pioneer farm saw. After 16 years of 4 cords of wood and year Using the then called optimal the saw stopped dead. After my dad took the saw apart he cleaned the outside of said parts and left them on the work bench. When I came home I looked at the cylinder which was like a mirror tube, brand new.Piston,rings all like new.I asked him later at supper did he already have the new parts on the bench.He told me that those were the old parts and that the saw stopped on account of a nut that came loose from the exaust (his fault).
I was so impressed with the lack of wear that now with my own saw Eco 5000 I have 23 hard years on it and the compression is still 150 p.s.i. what more can I say?