My old one is an Alko - had it 30 years, used maybe 4 times a year for odd jobs (pruning and firewood cutting - not felling). It's showing its age in various ways, the main one being that the auto-oiler failed a year or two back (following advice in this hallowed place, I currently oil it by dripping the oil on the sawchain every few minutes from an old washingup liquid bottle.)
I also have a Bosch electric saw (a Top Ten Tool), but one needs a petrol every now and again, doesn't one?
Where do I start? Don't know whether to splurge 150 quid or so (e.g. the Makita 35cm), or get one of those at well under 100 quid. Of course I can wade through the reviews on Amazon, but the voices of experience here are worth 100 Amazons.
My old one, and my electric one, are both about 35cm, which is big enough for everything I've ever done.
And while we're about it ... is there some Old Pro's trick to sharpening sawchains? It's SOOO tedious running the file over the teeth every now and again while doing a job!