What I believe is not being mentionend in this thread is the different type of oils used in bar lube and of course the resulting differences in price. The different type of oils would be
1. Dino = mineral oil
As far as I have understood, it is often used engine oil that has been idustrialy filtered and had takifiers added. This type of oil is cheap, usually in the 5-10$/gallon range. Of course it is also environmentally a major problem! And here in Europe more or less bannend in all public and larger privat forests. Even the harvesters, that lube their chains through the hydraulic systems, often require the non mineral oil type, as far as I have understood.
2. Bio = canola / rapseed oil
This is often blended with preservatives and takifiers so that it has, usually at least a 5 year shelf life. This type of oil is expensive, usually in the 15-25$/gallon range, when bought in premixed version. It is evironmentally not a problem at all. Here in Europe it is the main type of oil used.
The premixed "brand" version which contains takifiers, etc. is what I use only in saws with a bar length above 18-20inch. Below bar length I use just regular canola / rapseed oil from the supermarket. Just the cheapest brand, usually around 3 - 4$ a gallon. The lubrication is no problem whatsoever for shorter bar lengths so this is what I use a LOT. And for me there are absolutely NO price savings compared to the dino oil!
What can be a problem is that the canola / rapseed oil can deteriorate and harden (almost like a glue) when used only infrequently = once a year or less often. I use it in my regular saws but also have some dino=mineral bar oil at hand if the saw is then stored for prolonged time. I usually run the last filling then with mineral oil. This procedure is what I use in my less frequent used saws (f.e. contra, 040, etc.)
7