Wow--I'm not a chainsaw / lumberjack subject matter expert by any means--so take it for what it's worth--but I disagree. My experience with M18 16" has been great--have used it several times around my home, with neighbors, etc. on the smaller stuff, no issues at all. I helped a buddy take down a dozen or so 10"-ish trees including debranching and didn't have any overheating problems, or needing to swap out batteries (pretty sure I was using 8amp batteries).
It does leak chain oil though--that's annoying, but I haven't seen too many chainsaws that don't--always assume that's a price of doing business with chainsaws.