Ok So I Suck at shooting and I don't know jack about hunting either but I know a good bit about chainsaws and cutting wood....I'll try to organize a few thoughts and probably get longwinded anyway. Oh well.
7yrs running my own company as an Arborist and do 99% of my own repairs and maintenance on too many chainsaws. Brand loyalty is a thing in anything (I like Chevy more than Ford, and Tikkas) but when it comes to chainsaws I get asked often about what brand I like best and my answer is the sharper one. Definitely the #1 tip for chainsawing is keeping it sharp. #2 is minding your gas. I can only get ethanol pump gas so if it's a saw that might sit for more than a few weeks it gets "fancy gas" from a steel can (Stihl for consistency sake).
I've had good results with Stihl, Husky and especially impressed with the value and ease of maintenance of echo saws. I've had issues with all of them too. No saw will run well more than one good tank of gas without cooling off time if it's 110* and gas in the lines starts boiling. never leave'em laying in the sun around here. We'll wet a towel from the water cooler and cover'em up in the shade if I really need that saw to run again within an hr. Batteries suck in that kind of heat too, especially for big cuts but they are easier to cool off with a wet rag vs a gas saw.
I LOVE my Milwaukee tophandle(14") on climbing work. I do more trim work than removals and climbing around with an idling saw on my hip, or pull starting 100+ times a day for a few cuts at a time gets so old. Once I went battery It actually changed my quality of life. the newer Forge batteries are in fact significantly better. Need to run the 8ah. 12ah are too freaking heavy in the tree but good for the 16" rear handle saw on the ground. It's a lot heavier than the CS-2511T and It doesn't quite keep up with my 201T (16") but it's not too far behind. I only use the 201T for bigger removals where I can use more bar and it's been sitting in the garage for a while. The Milwaukee has power and torque and cuts to satisfy professional use. The convenience of the instant on battery is unmatched, and it doesn't have any filters to maintain either. I have been enjoying the uberlight echo CS-2511(12") again lately for small jobs and it is a pleasure going back to such a light saw on a climb once in a while.
Around here at least 80% of my work is on Mesquites, and if I get into a 60-70ft Aleppo Pine or Eucalyptus up 30"+ in diameter it's a notably Big tree. Diameter and job specifics (Felling, Bucking, Trimming, Dead tree, Live tree etc) makes a huge difference in what the best saw for the job is. Species matters a LOT too. Try cutting up dead Eucalyptus with aggressive depth rakers and you'll regret it. I set'em at .025 which is the max that works for me in dead hardwood all day without dulling too fast or binding. Then green trees or pine feels still feels like butter anyways. If you're in conifers or cut mostly live trees then file'em on down and let it eat if you've got the power to pull it through.
I don't have anywhere near the experience with larger saws that the logging or forestry guys do who live in timber country.
Stihl M-tronics saws have been 100% awesome for me. I bought a 201T, 362C, and 661C about 5 yrs ago and have had zero issues with them at all. They are some of my best cutting saws. My local Tech/Dealer says they are particular about having clean air filter. I keep filters clean(compressed air) as I do all my saws but I replace the filters on these a little sooner than regular carb saws. I also run Stihl premixed gas in these as i don't use them every week. regular workhorse saws (MS391, Husq51, CS-400) just get pump premium and it doesn't sit in them long enough to cause problems. Any saw that might be sitting for a few weeks or more gets the fancy gas and that makes a huge difference in avoiding carb woes.
I love my 50cc Husqvarna. 50-60cc is IMO the most versatile size for a do all saw. unless you actually NEED bigger or faster production environment. I started my company with a 55Rancher and a 20"bar. I wore it out, put on a $50 asian top end kit and ran it another year or two. Luckily I came across a barely used 51 in great condition and it's been even better, but I take better care of it too. (don't push dull chains through a stump to git'er done just stop and swap on a fresh chain or just grab a different saw that's sharp and not already hot from cutting the rest of the tree)
Sure if your a professional cutter you'll appreciate more bar and more power, but as a couple other guys noted fatigue is real too. I usually have at least 5-6 saws of different sizes in the truck on the daily and select the one that's just big (heavy) enough for most of the work at hand until I get into bigger cuts and reach for more horsepower. If your bucking up logs for firewood you may want 24-28"bar and 70cc+ but if your cutting small trees, limbing, or even cutting up 10-12" stuff I'll take a 20" 50cc saw.
The echo cs-400 with an 18" bar can do work, a lot of work, and has excellent durability and little maintenance. They just work when you pull the starter and they won't wear you out to carry it around cutting all day. If 18" is enough bar and 40cc power class that's the jam for me. lighter than the options I've had from Stihl or Husqvarna and it just runs without problems for years of heavy use. finally had to rebuild and eventually replaced a couple carbs but compared to how often I've replaced diaphrams on my Stihl saws the echo earns praise. My 2.5yrs employee has himself a CS590 and speaks well of it too.
That's probably enough outa me. I'll go back to my hole.