Let us not forget that I have a used 036 with the "QS" feature to consider as well. A fella I work with has it and is looking to sell. He says it is in good condition. He is asking $300 at the moment but I will see just what kind of shape it is in before making any offer. Is the best way to check the engine to pull the muffler off or are there better ways to inspect it? Of course I will run it after a visual inspection.
If you have a compression tester this would be the time to use it!
If the owner will let you, pull off the muffler and check out what little of the side of the piston you can see inside the exhaust port, then lower the piston and use a flashlight to look at the condition of the cylinder walls. Deep scratches MAY be a deal breaker, unless it's worth it to you to swap out a piston and cylinder.
You mentioned the types of wood, but not the size.
James; I have both the 028 and MS280 (albeit an older model that doesn't have the electronic fuel metering) and a 260 and recently got a near-new 361. This is the way they settle out
for me:
028 -- nice torque, good cutter, buzz bomb
280 -- wonderful anti-vibe, cuts like crazy, my go-to saw.
260 -- surprisingly nice small pro saw -- fast cutter with sharp chain. Might be overwhelmed by big wood.
361 -- after all the hype on the forum here, I found it to be disappointing. With a 20" bar I can easily bog it in down-for-a-year red oak that's about 17" dia. Chain is new Stihl.
Other notes: I bought a 20" bar for the MS280 and ran that for a while, but went back to the 18". It cut better and balanced out much better. I run the 028 with a 16" now, and it's happy, too.
Hope that helps.