I agree with Tree Sling'r on the definition of pro equipment. Its "pro" if you make money with it...its occasional user if its a hobby or firewood cutter. That being said, I think the issue is that the true professional users out so many hours on saws that things like being easily and economically rebuildable, and easy serviceability come into play. I was shocked how quick some of these logger types can burn up a saw even with proper maintenance to the point that it needs rings/piston etc. Also the argument that a pro saw used in an occasional use niche will last just about forever is also probably true if they are decently maintained. Its about how much you are willing to pay for durability, just like over the road and medium duty diesel trucks are built with an engine lifespan of 500K-1 million miles in mind before its first overhaul.... and at that the overhaul is easy(relatively) and inexpensive (comparatively)passenger cars and trucks could probably be made like that but people don't usually make money with their cars, drive that many miles on them, and they're usually tired of them after 5 or 10 years. Therefore the user would never pay the premium. So it is with the non pro quality saws. I'm not a pro...I use my Stihl saws pretty sparingly during the non firewood season, and for the work I do, they are great, they run when I need them to, but it would take me a long time to run 1200 hrs on one so its hard for me to swallow the premium for the pro saws, since I don't make that much money with them.