i have never run a chainsaw with a motor that big. dad used to have and old mccullough 66' with a 6' foot bar. used to cut down live oak stumps with it. that thing was a beast and made a sound like a cross between a helicopter and a chopped up harley.
we have one at work that has a 6' foot bar mounted onto a lil gas powered generator. the bar is set on a pivot, so we can use it to make exact cuts on entire packs of lumber.
there is just nothing quite like the smell of sawdust and bar oil while your ears are ringing.