Depends on how much you use it.
Here is my situation. I have small 17 acre farm in country with quite a few trees to trim branches on. I don't have a lot of heavy use here where I live in Condo. So I bought five 18V rechargeable tools from Black and Decker. I have Pole Saw, Chain saw, String Trimmer, Leaf Blower, and Hedge Trimmer. When I take Pole Saw and Chain Saw to farm I take all 5 fully charged batterys. By the time I run all 5 batterys down I am tired and ready to quit for the day.
That being said if I had much more regular use I would buy gas powered saws. The electric works well for me in my limited useage.
Oh and I was telling myself how smart I was getting all these units that use same rechargeable battery and what happened ? Black and Decker came out with same tools I have now with 32V Lithium Battery ! More power , longer run time and of course won't interchange with my 18V tools. Dang. Kind of like buying new car or truck like you have always wanted and then the next year they come out with new model that you want even worse !
Anyway rechargeable electric works for me and sure beats getting gas powered units started and running after setting all winter.Especially if I left gas in them ! ☺ ☺ ☺