I used to do chainsaw and small engine repair on the side, and I fixed and sold somewhere around 100 or so probably before my work got too crazy and had me out of town all the time, and no time left on the weekends or weeknights.
My $.02..... I love to sell Stihls, as they sell used for more than Husqvarna, Echo, or any other brand for that fact.... unless you have a rare Husqvarna, then you can sell to a collector or "chainsaw enthusiast" (yes, that is a real thing, believe me!!).
Do I like Stihls, Yes, sure I do. Do I like to work on them and fix them? No, but at least the parts are usually available if the saw was made in the last 30 years, not necessarily the case with the Husqvarnas or Echo saws.
Here are my opinions- with pros and cons of of gas vs. electric
Gas -
Pros:
1. As long as you have fuel mix, bar oil, and sharp chains, you can cut as long as you want
2. If you start with a big enough 2 stroke saw, you can install a shorter or longer bar on it to modify it to what you need to cut (l usually like to run 20 inch bars or longer because I don't like to lean over as much when I cut)
3. You can decide at what elevation you will most likely cut wood at, which will also determine how big of engine you should choose. A 40cc saw will work ok on small hardwood and medium sized conifers in Denver and similar elevation areas. You will want a 60cc or larger if you decide to cut wood at 8,000-10,000 ft. elevation.
4. A Professional series chainsaw will have a Magnesium engine case/housing, and they will last a lifetime if properly maintained and ran on non-ethanol gasoline fuel mixed with quality 2 stroke mix oil (or run canned pre-mix fuel and run it dry and drain the tank after use if you plan to let it set up for a year or more.
5. A professional series chainsaw can be repaired if a part breaks from use or mis-use/abuse.
6. A professional series chainsaw of 50-60cc will be set up to use a .325 sized chain instead of a mini-pico chain like the electric saws and sub~35cc saws use normally. The .325 chain with a round chisel pro-grade chain will cut waaaaay faster than the chain that the gas saws and electric saws come with. The chisel chain will dig harder and won't be as smooth to hold onto as "safety chain/low-kickback chain", but it will go through wood fast!
7. Users tend to respect a Gas chainsaw much more for safe handling
8. You can adjust a gas chainsaw for the ideal mixture at any altitude, otherwise, a saw set correctly for lower elevation will be way too rich if you go up to higher elevations, and it will have much less power than if it was adjusted correctly.
9. You don't have to purchase a very expensive spare battery like a battery saw would require, you just put more fuel mix in the saw and keep on going
10. In a "tough times" situation, you can run on somewhat mediocre gasoline and mix it with castor oil or even engine oil in a worst case scenario. As long as you don't run the engine lean, it will keep going.
11. Pro saws will have adjustable bar oiler pumps, and the user can run more or less bar oil lube, depending on the moisture content of the wood, and the hardness of the wood, keeping the bar and chain cooler with more oil in hardwoods.
12. Most Pro saws will use about one tank of bar oil to one tank of fuel, as a good reminder of when to stop and fill up the oil and fuel tank both together, as well as to clean the bar groove and oiling holes on the bar, and lube the roller tip with grease.
13. a Good pro saw will leave a pile of wood chunks/shavings at your feet pretty quickly
Cons:
1. If you use a dull chain and push too hard, or you have poor fuel with low octane (older gas that you are using) and push it too hard, you can overheat a gas chainsaw and score the piston and cylinder, stopping the saw and requiring a sometimes difficult and somewhat expensive repair.
2. If you adjust the High speed mixture screw, and get it wrong, you can lean out the engine and score the piston and cylinder
3. Many of the newer pro saws in the 50cc+ sized engines have auto-tune(Husqvarna)/ M-Tronic(Stihl) carburetors/fuel metering devices. You do not want a saw with these automatic/electronic systems, they do not work well at elevations and changing elevations, as they many times will not start back when hot at the end of a tank of fuel. There are still many new pro saws that have the good/old standard adjustable carburetors.
4. if you leave a gas saw inside of a truck or vehicle, you will likely smell fuel, as the chainsaw's fuel tank has an air-vent that will allow some fuel vapor release, especially if the saw is left in a hot environment with fuel in the tank. Another reason to drain out the tank after use.
5. Can be tough to start if poorly maintained or incorrect starting technique is used, easily flooded and won't restart without removing and drying the spark plug, and sometimes requiring replacement of the spark plug, so you should carry a spare.
6. Noise. Even the quietest gas saw is relatively loud.
BATTERY SAW-
Pros-
1. Torquey for the size and weight of the saw
2. no fuel smell if kept in a closed box or vehicle
3. quiet
4. No issue with hard starting like 2 strokes can exhibit
Cons -
1. Will you always have the battery charged when you need to use the saw? If you leave the battery charged all the time you will reduce the amount of power it will put out, and how long. Also, what if you aren't done cutting when the battery runs down? You will have to charge it to resume cutting. This isn't a possibility if you are way up in the mountains, at a campsite with no way to charge the battery, or no time to wait to charge the battery.
2. A replacement battery for the higher quality brand saws is very expensive, 50% or more of the cost of the new saw is not uncommon
3. Technology is ever-improving, and the buyers/owners of electric saws will fall victim to saw parts not being replaceable, or serviceable, batteries will die over time with lack-of-use and/or over-use.
4. Battery technology will improve, battery shapes will change and connectors will change, phasing out older battery saws in 5 to 10 years the way the technology changes things.
5. non-adjustable bar oilers on electric saws will not output enough bar oil in some hardwoods and can cause overheated bars and chains and increased bar wear requiring more frequent bar replacement
6. Users tend to forget to fill the bar-oiler tank on electric saws, and they ruin far more chains and bars than gas saws
7. Most electric saws use small "mini-pico" chains that don't cut much of a chunk of wood, almost more smaller chunks/sawdust cuttings
I can go on-and-on with this subject, so if anyone wants to hear more of my $.02, just ask.
I can tell you how to test a used saw to make sure it doesn't have any issues as well, if someone wants to know....