Former USFS forester/wildland firefighter rated at Class C faller, meaning up to and including the largest redwoods/Port Orford cedar/Doug fir...
I wear ALL of it.. every time. I now live in the southern USA, and believe me, I lose a quart of water every day I wear it all, sawing in July or August.. even WITH hearing protection I have a small hearing loss in my right ear.
Bottom line? Wear it.. or have GREAT insurance for your widow and children. I've seen the cuts from saws.. usually big Stihls or the fast running Huskys... you'll bleed to death in minutes. The main thing to keep in mind, is that uncontrollable kickback rarely happens when you are falling a tree, or bucking it up for firewood.. but limbing, or cutting stumps below 14" makes up about 60% of kickback situations. I've dropped cedars 200 foot tall and ten foot in diamter, humboldt cut, with hydraulic jack pushing, and not a problem.
However, when I cut brush on my own place... I spend MORE time making sure what I am cutting, looking for what my bull bar (for brush) could hit, than I do, making all cuts to drop a 200' tree. Why? Because thats when accidents happen.
Another thing.. please please... have EVERYONE who might be watching, spectating, applauding, stand at LEAST 2 1/2 tree lengths away from the base of the tree you are falling. All it takes is one perfect cut.. and you hit a dead snag, it goes over and hits someone.
In the Yellowstone and Montana fires of 1988 (remember ?) there was ONE fatality. Dead snag came down on top of a guy..
Stay safe..