I normally grind my chains on a Simington chain grinder. This grinder does a pretty good job and if you would like to learn more about that , I do have a video coming out about that soon. That being said, it is still very good to actually know how to chisel file using a hand file. This is a skill that has served me well and is indispensable in many ways.
It can turn a "bad chain day" ( that's when a guy dulls all his ground chains early in the work day) from a complete disaster , into a relatively productive day.
It gives you more freedom and independence when it comes to sharp chains. It can also save you from so much grinding, because once your good at filing, it's relatively fast, and it works great for touching up those wood dull chains and getting that nice sharp cutting chain back in action!

In this video I talk about some of the differences between a chisel ground ( or hand filed ) chain ....and a round ground ( or hand filed) chain.
There are pros and cons to both.
The biggest advantage to a chisel ground ( or hand filed ) chain is that it tends to hold its sharp cutting edge better and that is why most commercial timber fallers use chisel ground chain.
The biggest advantage to round filing is that it is a lot less of a learning curve and can be used successfully in many different cutting conditions.
It is probably the best option for cutting firewood, clearing brush, and can work pretty well in falling and bucking situations, but it will take more filing ( or grinding) then a chisel ground ( or filed) chain.