Echo saws are a good solid unit , they don't offer the best warranty out there for nothing at 5 years.
For a 8 Hour a day 5 day a week logging saw I would run either Stihl or Husqvarna's pro line.
But the way I look at it arborist tree work is kind of casual farm type saw use right ? From what little the average arborist seem to know about saws helps prove that too.
How many arbs or climbers run a saw 8 hour a day 5 days a week anyways? Echo offers a saw for any range of arb work besides a topnhandle like a Ms200 or 540 Husky.
But a little work from Mastermind Randy that TH Echo will do fine.
I field tested the twin cylinder 60cc Echo back in the early '80s logging. Found it was a solid very well built precision saw but wasn't designed for my timber falling work....would be the ultimate mid size farm or arb ground saw at the time though.