I found a 650 on my local cragslist. "Stihl MS650 chainsaw with big bore kit 98 cc extra cylinder extra had tons of accessories everything goes with it three bars all the chains ,files, oil, extra parts etc ". Bars are Stihl 20,28,36". He is asking $600 for it. For comparison in my area I can buy a new 660 with 28" bar for $1000. Does the 650 have the same bottom end as the 660?