First post on this forum. If this site has topics discussed as in-depth as this I am proud to be a new member.
Chicom, great breakdown on chainsaws. One short bit I would add, make sure you have plenty of spares on hand, extra oil for the mix and bar, spare bars, chains, spark plugs, filter's, etc. Proper chain sharpening equipment can be critical as well.
Funny that you mentioned the Scrench, I would suggest having 3-4 of them around. I went out to cut some trees a few weeks back and needed to adjust the chain tension and found I have misplaced the Scrench. I will have spars for it.