The advice given is excellent. Chainsaws are one place you generally get what you pay for. The homeowner saws are excellent for trimming limbs with most under three inches and they will take down the occasional tree. One thing I don't see mentioned is once the tree is down, those short bars and slow cutting chains are brutal on the back! Twenty-four inches of bar and the extra teeth make it far easier to work your way through a tree once it is down.
My opinion, a few hours a month and light work, the homeowner saw might be marginally adequate. Certainly adequate for a little pruning and the rare heavier use, as long as you don't tackle dried wood or major logs with it.
If you are going to use the saw more like ten hours a week, at least the farm and ranch saws. In truth while these aren't optimal they will do the job pretty much anything you tackle with the bar and chain that comes with them. You can also often change the bar and chain out to pro style bars and chains. These saws still won't hold up to hours a day usage as well as a pro saw but they fill the bill for most of us. A little extra weight and not quite the durability and build quality of a pro saw but probably a fine saw for typical usage.
The pro saws are meant for daily use, hours a day, for years. They are a no compromises top quality saw if you buy a Stihl or Husqvarna and some of the others aren't too far behind. Pricey and worth it if you are going to use a saw a lot.
One thing I haven't seen much focus on is safety. The homeowner saws are built for amateurs who rarely use a chainsaw. Few teeth and very unaggressive profiles are lousy for cutting but they are hard to make kickback and give you a faceful of chainsaw! The end guards that are riveted on some annoy the hell out of me but the bolt on ones aren't the worst idea for someone learning to use a saw. The farm and ranch saws have more teeth and more aggressive teeth. These saws aren't as dangerous as pro saws but it seems to me they are built with the assumption someone buying them knows how to run a saw. The pro saws are designed for professionals to cut wood fast and as easily as possible. The worst possible place for a beginner to start, naturally where I started many years ago! These things will hurt you in a heartbeat a dozen different ways. If I was a beginner with plenty of money to burn I would buy one of these but if just starting out I would buy one that could be downgraded with a farm and ranch style chain or chain and bar as needed. Like turning wood and most things, everyone makes mistakes starting out using a chainsaw and the pro saws are extremely unforgiving. Few old pro's don't have major scars as reminders. Used right these saws make green trees seem soft as butter. Used wrong, they make meat and bone seem softer than butter!
Hu